It would, but there are a bunch of PSone games you could get for $10 or less. Then there are the movies you can buy for about $5. Trust me, it'd be worth the buy.
It's worth it, unlike buying a 360 where you have to worry about everything. The only things you have to worry about with the PSP is keeping the system clean
and the screen free of scratches, both of which are best managed with a case. If you're a really, really big fan of Kingdom Hearts, I would at least suggest getting the PSP bundle with Kingdom Hearts when it comes out.