I'm on Windows 7, in French, so I also need to translate to English. Some of the items have changed names, some are in new places, and some new ones have been added.
"system protection" is a "new" Windows 7 title.
You obviously know your way around to a reasonable level. If you find the equivalent functionality on XP, then it's OK.
Using the "Run..." dialog, start "services.msc".
Look the descriptions for something about "saving" and "restore".
In Windows 7, the description reads: "Offers the capacity to save and restore Windows".
You should have something similar. Make sure that this service is set to "Automatic", or maybe "Manual".
Only about 70 Gb used on a 500 Gb drive, it's almost empty.
If you suppress all previous restore points, you have no restore points available. You used the correct procedure at the correct location to suppress the old restore points and restart everything.
Try creating a restore point manualy.
Install something, or uninstall something unimportant.
Reboot.
Restore the system to your manual restore point.
If the newly installed application is gone, or the uninstalled application is back, your restoration is working.
Keep only one system cleaner. More than one is overkill and can cause some troubles. I suggest that you keep Ccleaner. Make sure that you set it to NOT touch your restore points.
Several cleaners, possibly set to agressively, can destroy your restore points, or make them unuseable.
Also, only keep only ONE anti-virus. More that one anti-virus only bog you down and each one can interfer with the working of the other(s). MalewareBytes is prety good.
If you realy want to have more than one anti-virus, you MUST set ONLY ONE to run all the time, and only do manual scans with the other(s).
AdAware and Spybot are both excellent products and can peacefully coabit on the same computer. They don't hunt for exactly the same thing.
I don't see a third party defragmenter. You should get one. There are many very good free ones around. To be set on a weekly schedule. If you get a premium one with some kind of "smart scheduling" or "set and forget" feature, enable that feature.
Almost ANY defragmenter is beter that the one provided with Windows.
Electro, May 2013