Here are some of my favorite software titles I use.

I use all these programs and have had no problems.  Be sure and back-up your data
and create a restore point before you run any of the cleaning programs.  Don't blame me
if these cause any problems for you, use at your own risk.

For A timer I use Timeleft.   You can download it here  http://www.timeleft.info/
You'll have to enlarge the timer box and change the font to Times New Roman so it's readable.

If your computer is running really slow, try these programs, I use them on all my computers.

CCleaner  -  http://www.ccleaner.com/     I run this often

Advanced System Care - http://www.iobit.com/advancedwindowscareper.html       I use this often.

Eusing registry cleaner - http://www.eusing.com/free_registry_cleaner/registry_cleaner.htm
 I've recently found this one, seems to find registry entries that the other programs do not.

Check back, I intend to make some tutorials on these.