Yeah, Tiger Definitely.
I had the exact same computer (same ram and processor and HD and everything) before I switched to my MBP.
If I were you though I'd turn off Dashboard. Whenever I would accidently click it and widgets would open, my system would be noticably slower and the fans would go much more then before and until I quit.
Other than that that thing should do all you want it to and more. I regularly used photoshop and flash as well as all the iwork and a variety of other media programs with little to no hitch.
That is in really good condition too! Great find! Be careful about the paint on the off white part, that tends to always chip on all of them, so be careful. Also watch the hinges, They were known to snap on that model. You don't have to baby it at all times, just make sure to not put any undo stress on it.
enjoy your lappy!
Edit: WHOA 300??? that's a great deal! I sold that same computer in a little less of condition for almost 600 last year, and I see them regularly for 450+ in worse condition. GOOD BUY!