I "met" Brent Spiner for the 2nd time yesterday (my first being about 5 years ago).
And that guy is an absolute hoot. He is a true entertainer, not even when on stage, but as we were waiting in line for his autographs. He'd pretend to recognize someone as a stalker, then run around asking for security, baffled as to why they weren't showing up. At one point, he stood on his chair (which didn't look THAT sturdy), looked across the aisle to where Olivia D'abo was signing, and tried to get her attention, asking him to call him, they should go out some time... and then we finally got to him and he just had us laughing the whole time. I can't speak more highly of him!
My second favourite was JG Hertzler, who acted in character of Martok when I told him how honoured I was too meet the leader of the Klingon empire (he wasn't in costume, but he didn't need to be!) He stood up, slapped my shoulder and told me the honour was his.
I also have high praise for Avery Brooks. We were a group of about 9, it was the beginning of the day, and he took the time to learn all of our names. THEN, as we were leaving at the end of the day, he was randomly passing by us and stopped to individually tell us all good-bye... stumbling on only 1 of the names!!!!
I've met most of the TNG cast now (just have Sir Patrick Stewart to meet) and have no complaints about any of them, they're all genuinely friendly people.
Shatner was a blink and you miss him encounter, understandably, they had a huge lineup for him.
I think the closest I have to a negative experience was with Robert Picardo. It was the end of the day, also the end of a 3 day convention, and I went up for an autograph, almost literally last minute before the convention was over. His disposition was pretty neutral, but he specifically asked "You don't want me to write any of my phrases or anything I hope?" I said nah, that's cool (I generally let the actors sign what they want to sign), and went on my way. BUT I attribute that to a tiring or off day, or even my last minute autograph grab, because I've heard too many good things about him otherwise.
