Go into task manager, have a look at what processes are running. That will give you a good idea of the amount of $hit that Windoze is running in the background
Cheers tomfun. Task manager has done the trick. It led me thro' the process step by step. Thanks for ALL the suggestions everyone.
I read that to the tune of Sparklehorse's "Hammering the Cramps" from the album 'Vivadixiesubmarinetransmissionplot' (http://www.youtube.com/watch?feature=player_detailpage&v=RO3Kly8Gssg#t=45s). I think it really added something to your post.
If you type something like 'msconfig' in the start/run box that lets you choose what programmes start when windows does, can make a big difference turning a lot of these of, like you don't need iTunes running all the time etc. If you haven't got a solid state drive see about getting one, they aren't that dear now and the general speed difference is amazing.