This one's got pretty positive reviews and is in your price range:
Newegg.com - HP G61-320US NoteBook AMD Athlon II M300(2.0GHz) 15.6" 3GB Memory 250GB HDD 5400rpm DVD Super Multi ATI Radeon HD 4200 - Laptops / Notebooks

Keep in mind that gaming on laptop is more limited than on desktops, and this kind of performance can really drive the price up. There are very few sub-$700 laptops that are good for gaming, not that many more sub-$800.
Last, the Inspiron 15 uses an intel video card, which I would personally stay far away from. Ati? Not a fan but they do make good performance cards. Nvidia? Sign me up. Intel? Nowai.