The Best
LOST- Pure epicness that I honestly felt was the perfect way to end the show. I was worried that the show would slap me in the face with it's finale, and was so happy with what I saw on my screen that night. It was beautiful, spiritual, and just perfect...and I don't care if I'm the only one who felt that way. I wouldn't want it any other way.
Avatar The Last Airbender- Again, very epic and satisfactory. Left me on the edge of my seat, and blew me away.
Firefly- While I would have been happier to see this gem of a show continue on television, I have to admit it was pretty awesome to see Serenity on the big screen. I laughed, I cried, I was on the edge of my seat. Very happy with this ending, even though I still want more.
Boy Meets World-Just a really nice way to end such a great show, I hope we get the whole thing on dvd someday!
Terminator: The Sarah Connor Chronicles- Mind-blowing, and IMO a perfect way to end the show and leave the rest up to the fan's imaginations. What a great cliff-hanger, but it also acted as a satisfactory conclusion as well. Still holding out hope for a DTV movie though!
Scrubs- Season 8's finale may not be the official series finale, but to a lot of fans, myself included, it was. And I thought it was really sweet. I got a little teary-eyed when JD gets a flash of what his future could be like, and Dr. Cox's speech regarding him when he didn't think JD was there to hear it. Loved it.
The Worst
Dead Like Me- I couldn't believe how awful the tv movie series finale was, wow was it bad. All the reapers, aside from George, were bastardizations of themselves (don't get me started on Daisy...ugh!) and the plot was mind-numbingly stupid. I did like George's side-plot though, and the very end when she gets her promotion...too bad the rest of it stank!
Xena: Warrior Princess- The whole final season was awful IMO, but the finale took the cake. You could tell the writers were grasping at straws, they should have ended it with the previous season.
Dollhouse- This lacking show had an equally lacking finale, the big twist revealed in the last few episodes had me rolling my eyes with it's "we're just throwing this in there for the sake of a twist, we didn't really give it much thought" reveal (very much like the twist in the season 3 finale of Bones-a twist for the sake of ratings, not for logical or good storytelling). The final episode itself was rushed and lacking, and I found myself not really caring at all. To be fair though, I've always been somewhat bored with this show (overly focused on Echo, who doesn't carry the show that well)-but I imagine I'd be even more disappointed with the finale if I were more invested with the series.