Since we've delved fairly deeply into the negative side of meeting actors at conventions, I thought it might be nice to balance things out by everyone sharing their best experiences.
In no specific order, my best experiences have been...
Tim Russ - Met him while Voyager had just gone on hiatus from season 6. He was delightful. Warm, personable, friendly, energized to be there. He had a little skit he did where he had fans join him on stage to read the different parts, and I got picked. I was 15 at the time, but I'm quite tall and was then (I was about 6"7 then) and initially picked to be the Klingon, but he switched me to be a Starfleet guy (which turned out better cause I had a funny line then). After word, he signed an extra cast photo for me and then had Garrett Wang do the same, which is why all these years later I've got a complete season 6 (Jeri Ryan years) and a season 3 absent only Lien (Kes). He also slipped up and let me keep the script to his skit, which I still have and have never let anyone else see, as I mentioned this in an e-mail to his fan-club, which at the time was run by his sister Angela, and she swore me to secrecy.
Avery Brooks - Avery has a great energy. He's warm and enjoys his fans. I've only ever seen him be less-than-awesome once, and on that occasion he simply seemed over-shadowed by the other four captains rather than unhappy or distant - rather he just seemed to be letting the others do their thing rather than try to elbow them for some spotlight. Avery is so smart and so deep, you can understand why he's a professor at Rutgers. The second time I met him, he stopped to ask to shake my hand - normally the fan has to ask for such. That's the kind of guy Avery is in my experiences with him.
Robbie McNeil - met him along side Bob Picardo, Roxann Dawson and Ethan Phillips in the summer of 2000, no long after I'd met Tim Russ. They where just back in production of season 7, I believe. Well the convention itself was interesting - as in Chinese interesting ("may you live in interesting times") - the 2000 RNC was happening at the same time, same city (Philly) and some delegates where staying at our hotel. Well I can't recall now if it was Friday or Saturday, but we all ended up being evacuated because the governor of Illinois had sent his delegates alarm clocks in the mail. Actual alarm clocks. That ticked. And so ticking package to politicos = bomb threat.
Robbie, Armin Shimmerman and Rene Auberjonis where the only ones there at the time, and Robbie and Armin really went above and beyond. They held court, posed for photos with everyone, and really just made the whole ordeal tolerable and even fun. This was in juxtaposition to Rene, who had just done a role in "The Patriot" with Mel Gibson and newcomer Heath Ledger a month earlier, and stood off to the side surrounded by an entourage of convention organizers keeping us guests away from him 
Alexander Siddig - told some of the best stories I'd ever heard, ones that stick in my mind a decade+ later. Though some may not have been appropriate or appealed to everyone's sense of humor, lol.
J.G. Hertzler + Bob O'Reilly - if you've ever seen them at a convention, you know what fun they are. They've taken to showing up in make-up and costume at times. They're just fun and a good duo and leave to glad to have met them.
Jimmy Doohan - What a great man. You should all read up on Jimmy, especially if you can find his auto-bio "Beam me up, Scotty!". Anywhom, he was just a gem. Warm, friendly, nice, signed an extra thing for me (when I was a teenager, which is when I met the lions share of the actors, I could easily get away with that - acquiring an extra autograph. Don't know why!). Told great, funny stories. Did so much for his fans. I've never heard anything negative said about Jimmy. Not once, ever.
Alice Krige - I've never met her, but a friend of mine did, and the fact that I have some truly epically-inscribed autographs from her is a testament to how cool she is. She's one of the very few people I've not met that I'd climb mountains to. Sadly, she hasn't done a con in my area since 1998.
Nana Visitor - She really loves Kira, and it shows. The way she talks about her, it's like she exists somewhere else and yet is part of her, too. It's a unique way that isn't at all odd like it may sound. Always has good stories, and is just a friendly presence.
Kate Mulgrew - Always lively, always thought provoking, always honest. She gets into politics which isn't always appreciated by those who don't agree with her, but she's the captain gods damnit, she's entitled! lol. And most Trekkies tend to fall into the spectrum of agreeing with her, so it's rarely an issue.
In no specific order, my best experiences have been...
Tim Russ - Met him while Voyager had just gone on hiatus from season 6. He was delightful. Warm, personable, friendly, energized to be there. He had a little skit he did where he had fans join him on stage to read the different parts, and I got picked. I was 15 at the time, but I'm quite tall and was then (I was about 6"7 then) and initially picked to be the Klingon, but he switched me to be a Starfleet guy (which turned out better cause I had a funny line then). After word, he signed an extra cast photo for me and then had Garrett Wang do the same, which is why all these years later I've got a complete season 6 (Jeri Ryan years) and a season 3 absent only Lien (Kes). He also slipped up and let me keep the script to his skit, which I still have and have never let anyone else see, as I mentioned this in an e-mail to his fan-club, which at the time was run by his sister Angela, and she swore me to secrecy.
Avery Brooks - Avery has a great energy. He's warm and enjoys his fans. I've only ever seen him be less-than-awesome once, and on that occasion he simply seemed over-shadowed by the other four captains rather than unhappy or distant - rather he just seemed to be letting the others do their thing rather than try to elbow them for some spotlight. Avery is so smart and so deep, you can understand why he's a professor at Rutgers. The second time I met him, he stopped to ask to shake my hand - normally the fan has to ask for such. That's the kind of guy Avery is in my experiences with him.
Robbie McNeil - met him along side Bob Picardo, Roxann Dawson and Ethan Phillips in the summer of 2000, no long after I'd met Tim Russ. They where just back in production of season 7, I believe. Well the convention itself was interesting - as in Chinese interesting ("may you live in interesting times") - the 2000 RNC was happening at the same time, same city (Philly) and some delegates where staying at our hotel. Well I can't recall now if it was Friday or Saturday, but we all ended up being evacuated because the governor of Illinois had sent his delegates alarm clocks in the mail. Actual alarm clocks. That ticked. And so ticking package to politicos = bomb threat.
Robbie, Armin Shimmerman and Rene Auberjonis where the only ones there at the time, and Robbie and Armin really went above and beyond. They held court, posed for photos with everyone, and really just made the whole ordeal tolerable and even fun. This was in juxtaposition to Rene, who had just done a role in "The Patriot" with Mel Gibson and newcomer Heath Ledger a month earlier, and stood off to the side surrounded by an entourage of convention organizers keeping us guests away from him Alexander Siddig - told some of the best stories I'd ever heard, ones that stick in my mind a decade+ later. Though some may not have been appropriate or appealed to everyone's sense of humor, lol.
J.G. Hertzler + Bob O'Reilly - if you've ever seen them at a convention, you know what fun they are. They've taken to showing up in make-up and costume at times. They're just fun and a good duo and leave to glad to have met them.
Jimmy Doohan - What a great man. You should all read up on Jimmy, especially if you can find his auto-bio "Beam me up, Scotty!". Anywhom, he was just a gem. Warm, friendly, nice, signed an extra thing for me (when I was a teenager, which is when I met the lions share of the actors, I could easily get away with that - acquiring an extra autograph. Don't know why!). Told great, funny stories. Did so much for his fans. I've never heard anything negative said about Jimmy. Not once, ever.
Alice Krige - I've never met her, but a friend of mine did, and the fact that I have some truly epically-inscribed autographs from her is a testament to how cool she is. She's one of the very few people I've not met that I'd climb mountains to. Sadly, she hasn't done a con in my area since 1998.
Nana Visitor - She really loves Kira, and it shows. The way she talks about her, it's like she exists somewhere else and yet is part of her, too. It's a unique way that isn't at all odd like it may sound. Always has good stories, and is just a friendly presence.
Kate Mulgrew - Always lively, always thought provoking, always honest. She gets into politics which isn't always appreciated by those who don't agree with her, but she's the captain gods damnit, she's entitled! lol. And most Trekkies tend to fall into the spectrum of agreeing with her, so it's rarely an issue.
