You say its got to be up to spec, now if your not gaming on it then theres no point spending 200 on a processer.

Id get something like this http://www.ebuyer.com/UK/product/94640/rb/25141902177

Now im just assuming your motherboard is a socket 939, if it is that processor above will fit straight in, and it will come with all the fans etc and everything it needs to run, if you dont have a socket 939 mobo then get one of those(there not much so dont worry)
Then get 2gigs of ram http://www.ebuyer.com/UK/product/114484/rb/25142031754

Then a decent case, ive just brought this beast http://www.ebuyer.com/UK/product/118268, it has loads of room for all your components, looks good, built well, keeps everything cool which is a big plus

Basically with that processor and 2GB's of ram will be a huge speed increase over what you have now

As i said though the processor and ram will be fine assuming you have a socket 939 mobo, if you dont then you will need one to fit the above items, plus to get any kind of performance you need at least a 939 board

EDIT i forogt a PSU, this is the one i bought a month ago http://www.ebuyer.com/UK/product/102953 this one is great, the BMW of psu's

And fans dont worry about that, get a decent enough case like the one i posted and it has fans built in, they are huge and easily keeps my system cool which is pretty high spec