I bought myself a Dell Inspiron 14R (N4110)
last year for college, and haven't been disappointed a bit. I got it for $400 (i5-2410m, 500gb 7200rpm, 4gb RAM) through Dell's Outlet Store, which I HIGHLY recommend if you're going to buy Dell. All of the options there are just as good as, if not better, than a brand new laptop.
Now, I don't exactly remember the battery life it had when I had just received it, but from a full charge on the Balanced power plan, I get about 2.5 - 3 hours running a few light programs and number of background applications.
The Inspiron 14z that WR2 posted actually looks fantastic - it's got a more powerful processor than mine, the same resolution and IGP, but it's thinner and lighter. There's none in the Outlet right now, but it doesn't seem like the 14z's price would go that low in the Outlet, so you may want to go for this deal.
Regardless, Dell Inspirons are good home-use/college-use type laptops, and they're within your price range. I've not dealt with many brands apart from Dell (concerning laptops), but I've had serious issues with HP laptops (having basically every part fail). I'd advise you to shy away from HP if you can.