320GB HDD, I believe its 15.6 inches or close to that, max resolution is 1366 x 768, and i'm pretty sure it has a traditional screen.

My laptop has a ATI Mobility Radeon HD 4500 card (I'd imagine that would be slightly better than 4200? Who fucking knows. lol) and telling from www.canurunit.com, it's not good enough to meet The Witcher 2's minimum specs. Starcraft 2 should run fine on your laptop I'd think. Blizzard is known for optimizing their shit.

My Laptop runs with 6GB of DDR3 with an ATi Mobility Radeon HD 5870 intel i7 quad core and still stutters with some games on max settings. So I doubt you'll be able to run Starcraft or any other game on max settings. But it sounds like you should at least be able to play some games. The fact that it is a laptop makes it a lot harder on the system as someone mentioned above. Even with okay specs. Your laptop is far below the industry standards for todays games, especially trying to run them on high settings. Still for that price, sounds like you got a steal and should be able to enjoy plenty of games. 

Oh dam, here I thought you were going to say like $600 and I'd let you know how badly you got ripped off.

Just thought I'd peep in about this.  Gaming laptops don't have to be overly expensive.  You can buy for aruond $900 a 2.0 ghz quad core dual threaded i7, 6gb of 1333 mhz ram, 1gb dedicated graphics card, 16" screen.  I know this isn't an epicly amazing gaming computer or anything, but something like that can handle some good shit.  Mine is an older model of that and I easily run high on starcraft 2.

whats the battery life on it? 4 hours max. 

Most gaming laptops, mine included, as I mentioned above an i7 quad core, 6GB DDR3, Radeon HD 5870... Are always plugged in. To get max performance, max FPS, ect, it MUST be plugged in. Most people who buy a gaming laptop it is to be in place of a gaming desktop. I take my computer to my parents house, to my friends house, where ever I go and it is ALWAYS plugged in and is NEVER an issue. If you are taking your computer camping, which I don't see why you would, I could see you having a problem with having it plugged in. Other wise it is a complete non issue. Thus battery life is a non issue and shouldn't even be discussed if you know anything about gaming laptops. 

quick little search

http://www.notebookcheck.net/ATI-Radeon-HD-4200.20493.0.html

The HD 4200 is onboard graphics card so it will use the somewhat limited RAM all your other things will be using. I don't think you will be able to play most recent games too well. I could be wrong though.

Honestly that's a poor machine. Much weaker than an X360. Expect to play all games on low settings except for Starcraft II perhaps on medium. And The Witcher 2 is unplayable obviously lol.

thats wrong right there. 

I dont see an better processor and more ram == much weaker than X360.