Here are a few hints which I have found useful for helping windows.

Going into start menu, clicking RUN and then type " msconfig " then enter. This brings up your configuration and startup menu. It is very useful for disabling startup processes/programs.

Additionally i find it very usful to lower the virtual memory on a PC when you have lots of RAM. Considering how much faster ram is than Hard Drive memory, use your ram and not your hard drive!

Also windows has alot of "Pretty" gui interfaces, which you dont really need. Just disabling all the options to make toolbars and menus appear simpler can aid in making a PC faster.