i would suggest that you get a ps3, i think that you can more out of it than you will out of the psp theme
PS3 - Can plug into TV with lots better graphics, have blue ray etc. PSP - Portable, small screen, battery kind isn't that good. It's really personal choice, I'd say PS3 though mate
PS3 of course, psp is good for a hand console but when it comes down to it I rather be playing against my friends
PS2 is an old console and at any time PS3 is much more better. However, if you go for PS2, you get it for a cheaper price, game titles can be bought from Amazon or eBay for cheap. This will save you a good deal of money. But to get that new generation gaming experience, PS3 is the real deal.