I've been collecting lots of Trek DVDs recently. I hope to get them all one day (if shelf space and wallet space allows for it, of course).
I currently have:
All three seasons of TOS remastered
TNG seasons 4, 5, and 6
DS9 seasons 4,5,6, and 7
VOY seasons 3 and 4
ENT seasons 3 and 4
All of the movies (including XI)
Borg Fan Collective
Klingon Fan Collective
Time Travel Fan Collective
So a fairly big collection, then. I'm halfway there, actually. Only 14 seasons out of 28 still to go!
Oh, and I'd like to get TAS as well, but can't seem to find the DVD set in stock anywhere anymore.