#27 - Jak 2 (PS2)
As guessed by Veknoid. Jak 2 was the first time I ever played a GTA-style game (I didn't pick up that series until San Andreas) and as such it was like a completely new experience to me, I just loved exploring Haven City and hijacking cars, going on random Krimson Guard killing sprees :D. Add in a fantastic mix of platforming inspired by Jak 1 plus a whole host of guns and it made a really enjoyable game.
Clue for my #26 - Third in a series but actually a prequel of sorts, mainly a PC game but appeared on the PS1 (which is where I played it).