Ok that processor you have as you said is 2.2ghz im positive it only has 533 FSB. This processor is very old, persoanlly i would replace it.
I know the processor is the problem, is this computer Dell or HP? With that type of processor im sure the company you got this computer from didnt put a very good video card, im thinking a 64 bit. This computer sounds old.
I persoanlly recommend you to just built a brand new computer. With a processor such as that it will have alot of problems using modern applications and video games.
With a new processor your gonna need a new mobo obviously, and i think you should get a video card too. Im sure your sound card is out of date too.
I can easily find you all those parts witch will work togather. For case i would go ith a Thermaltake here is a Mid Tower case that would fit an Intel socket 478 mobo like nothing.
Heres a processor i recommend for you