I recently bought a Zalman Dual Fan CPU Cooler(http://www.tigerdirect.com/applications/SearchTools/ite...) for my first pc build. I accidentally used all of the thermal paste that came with the fan(I think it was ZM-STG2). I only realized my mistake after I watched some tutorials on Youtube that stated that a bit of paste that's the size of a pea was enough. I have spread the paste over the CPU with a piece of plastic and set the fan over it. I haven't checked to see if it leaked yet but if it has can I use this to clean it?(http://www.newegg.com/Product/Product.aspx?Item=N82E168...).
you can use this or 90% alcohol and a microfiber cloth as you dont want lose threads to get into your sensitive components
here is a good method on applying thermal paste http://www.youtube.com/watch?v=-hNgFNH7zhQ
i would use mx-4 there is nocure time as artic silver 5 there is around a 3 week period until it is completely bonded and mx-4 is better than mx-2 http://pcpartpicker.com/part/arctic-cooling-thermal-pas...
and always make sure you are using a non magnetic screwdriver and also make sure you are grounded so as not to conduct static electricity