Alright mate welcome to the forums
With cooling it depends how extreme you wanna go?
You could go the watercooling route if you like nice & quite, plus you would probably get an extra 100 - 150 Mhz overclock with a good setup!!!
Or the phase change route, either a Prometeia 2 or a vapochill LS, these systems last for years & are great value for money, you can get a £100 cpu & make it run faster than the £700 cpus, with your x2 3800 there is a chance of the dreaded coldbug but not many 3800 suffer from this which is good, with a phase change system you could probably get upto 3Ghz, which will give any system a massive preformance boost!
Hope this helps a bit!
Dave