Step 1: Disable Transparency
Choose Windows Color And Appearance
Uncheck Enable Transparency
Step 2: Disable the Animation for minimizing and maximizing windows
Click System and Maintenance
Select Performance Information and Tools
Click Advanced Tools
Click Adjust The Appearance and Performance of Windows
Uncheck all of them except for Use Visual Styles on Windows and Buttons
Step 4: A few tips
Registry Cleaner also works well for this.
Another thing is viruses. Vista is very secure but you always need to be conscience of what your downloading. Websites that have Keygens, Cracks, or Serials are usually dangerous. I recommend AVG because it is the best. It finds all the kinds of Viruses. Most hackers are trying to break in through Norton because many people have it. It also comes on most computers. I reccomend buying AVG because the freeware version finds things but is not always able to clean them. Also, even though AVG gets spyware, I like Spyware Doctor or Spysweeper just in case. The freeware version of spyware doctor is herehere.
Defragmenting every now and then isn't a bad idea. Also, disk clean up helps. These can help you if you have limited disk space as CCleaner does.
Last but not least, always update your computer. This will patch problems and improve your security.