wikiHow has possibly hundreds of "speed up your pc" articles; I have distilled that to three, tossed in some
CCleaner (by Piriform, with free registry cleaner, that thing everyone is trying to sell you. This has been Filehippo's most popular DL for years), a little
Spybot...and viola', a blazing fast dinosaur. I have used all the links included in the articles, MLin's are great (startup dashboard, etc.), but heathen newsletter/discussions (porn).
May this blaze your uploadedness.
http://www.wikihow.com/Speed-up-a-Windows-XP-Computer
http://www.wikihow.com/Disable-File-...-on-Windows-XP
http://www.wikihow.com/Double-Your-Internet-Speed
The top one is pretty comprehensive, and only lacks the other two, which are both single operations, and optional (tho effective).
I'd appreciate a note on anything I've missed, ty.