1. Clear your junk. Uninstall programs that you hardly use to
free up space. Not enough hard disk space will slow down
Windows.
Also clear any temporary files.
2. Defragment your hard disk. If your files are all over the place,
Windows is going all over the place to piece up your files and it
can take a long time.
3. Have more RAM. Windows is a RAM sucker despite having lots of
tweaks.
4. Don't have a wallpaper. Nice cool looking wallpapers only slows
down the system. Plain colour will do.