I'm not exactly sure why I said that you need to build a new computer lol. You certainly do need more RAM, but your CPU is fine.
ild. Anyways, you could easily upgrade to 8GB of RAM and put a new GPU into your PC for under $200. Look for at least a GTX 560; you can find those used, for under $100 sometimes.
Lol .. and i can upgrade ram to 4gb only and gtx 560!?! nah its out of my budget man india is different