Google shows that this problem is quite widespread. One of the comprehensive solutions found on Googling is below.
i. Check whether Volume Shadow Copy Service, System Restore Service is started and Set to Automatic
1. Type Services.msc in Start Menu search box, hit Enter.
2. Make sure that the Volume Shadow Copy Service is Running and set on Automatic.
3. If the Status of System Restore Service is not Started, Start it. Also set it on Automatic if it is not.
4. Restart your computer and try to do a system restore.
ii. Check how the computer works in safe mode. If the computer works fine in safe mode, then do a clean boot. The procedure to do a clean boot is at How to troubleshoot a problem by performing a clean boot in Windows Vista or in Windows 7
iii. Run the System File Checker (SFC.exe) to make sure system files are intact. Follow the steps below.
1. Click Start, and then type cmd in the Start Search box.
2. Right-click cmd in the Programs list, and then click Run as administrator. If you are prompted for an administrator password or confirmation, type your password or click Continue
3. At the command prompt, type "sfc /scannow" without the inverted commas and then press Enter.
If all the above fails then the only option left would be to start again by clean reinstalling Windows 7 and then staying away from WinCleaner.