XPfree is an optimisation resource for XP, Vista, Windows 7, 8 and 10.
About me: I program, have a BSc in Comp Sci & troubleshoot computers as a job. So I have some idea of what I'm talking about.
I live in New Zealand which as you may know, is somewhere near the penguins.
Hopefully these guides help you.
Simple Speedup Guide v1.5 - A simplified cleanup/speedup guide for novices. No rough edges or sharp corners
Speedup Guide v3.4 - The full guide for more comprehensive cleaning and speeding up
Additional tips v3.4 - Extra information for tweakheads