The Dell Vostro 3350 only has a AMD HD 6470M GPU, which is very weak, it barely beats the integrated Intel HD-3000 on performance, though it does offer DirectX-11 support.
If you go with the cheaper Vostro 3450 (14" screen) you get the AMD HD 6630M GPU, which is very close to the Nvidia GT 540M in performance... this will be a LOT better for playing games.
Alternatively, you could go for a higher priced Sony Vaio SA model, giving you a 13" screen combined with the same AMD HD 6630M GPU, and even an Intel i7 CPU. This notebook only weights 1.5 lbs, making it very portable, and the keyboard is as good as the Vostro keyboard.
The Sony SA models come configured with SSD on the Sony's web shop, but that really drives the price up... the configurator allows you to swap it for a 500GB platter and reduce RAM to 4G, dropping the price by more than 400 Euros.