Third person, hands down. Something about first person view doesn't meld well with my brain & I have trouble with anything that requires anything resembling quick reflexive actions in first person. Puzzle type things I can muddle through. Basically, I can play Portal but not Halo.
Oddly, this problem does not transfer to cockpit view games, despite still being first person. I mean, I'm still not good, but I can play something like Jumping Flash alright. I think it's a weird mental block- in a real cockpit, if you want to look around, you have to move the cockpit. But a person can look around just by moving their eyes, not their whole head. I think that simple difference makes moving in a first person cockpit more intuitive for me.