Yes that will be a great gaming system, though personally I would drop the Raptors for two higher capacity drives. The real life performance difference is minimal, but if you like your load times to be fast (that's about all they'll do) then they might be the right choice for you.
And Yes get 2GB of RAM, this is arguably the best 2GB kit on the market .
http://www.newegg.com/Product/Produc...82E16820227210
And just as an alternative to show you in case you weren't aware.
This quite air cooled heatsink does better than many watercooling setups.
http://www.newegg.com/Product/Produc...82E16835118223
I'm just linking that for an idea of something with a bit less maintainance.
Also, what PSU are you looking at. Don't skimp!! Expensive doesn't always mean good, and good doesn't always have to be expensive.