Apart from the fact that you cannot buy a 3.6Ghz CPU, except possibly a second hand Pentium 4 (Unless your talking the ebay nonsence, which multiplies actual core frequency by the number of CPU's)...
As a gamer, a 2.66Ghz Core 2 Duo "Dual Core", combined with 2 GB ram, and a 32bit OS... The best way to make sure of high performance, is a good graphics card. The CPU has fairly minor effect on games played at high resolution once your up to a certain point.
Sure a higher speed CPU, or a Quad core would show performance gains in an artificial benchmark like 3DMark, but in real games, very little gain.
If you have a 64Bit OS, then 4GB does smooth things out, as 64bit applications (including the OS itself) generally take a lot more ram to get the same job done. Even 64bit XP uses almost 600 meg, just for the OS + a web browser.
Even the most basic PC can handle web browsing just fine, faster broadband is the only real way to improve performance there, so that just leaves the gaming.
Are you looking for an upgrade, or a new system, if its an upgrade what spec is your current system anyway.