it could be overheating, but the sheer amount of processes screams of a virus/trojan/etc or just a unmanaged windows install.

I would get your external drive transfer your music off and any other stuff you want to keep.
and reformat and partition your harddrive for atleast 2 partitions one for windows and one for your music.
install windows and do all your updates. install antivirus and then check your external drive then transfer your music over to your other partition so that if you loose your windows install again you wont loose your tunes too.
I usually give windows 10 gigs nowadays for it and all the programs you install .
also do a control panel> administrative tools> services and shut down things you know are not going to need. there isa listing of unneeded windows services around on the internet.

also like stinky said do start run msconfig and deselect stuff you dont want to start.
since your computer is old like mine they need the fat trimmed off to keep up.
also dont use themes change to classic windows theme
try to keep system tray down to only the few things you really need.


I know i have the more radical approach but with all the crazy virii running around it doesnt hurt to be safe.
good luck