A little less than 50%.

I know that mine's pathetically low, but that's because of the collector in me, coupled with the fact that I get so many RPGs that take time to beat. I am, however, pretty sure I'm over 90% for games I've started...

I beat around 60% of the games I buy, haven't rented a game since the SNES and don't plan to.

I do have a lot of games that remain unbeaten that are really not beatable (off my head I'm thinking Wii Fit and stuff like that) so that brings my percentage down.

But also a few select games (Final Fantasy Tactics, LOZ: LttP, Super Mario World, etc.) I beat like once a year and have beat more than a dozen or two times.

I beat about 5% of the games I buy. No joke. I need to stop buying games, play a little less COD4 online, and start getting cracking on many of my titles.

100%. I want to beat them all, even if they suck.

While I'm not that bad, I too buy too many games compared to the time I have to play them. Last year I purchased ~40 games and I would have been lucky to have finished 10 of them. I'd say another 10 of these haven't even been played yet...

Buy - 90% first party, 20% 3rd party
Rent - 0% First Party, 0% 3rd party