Nothing about cracking, just a problem

[squareD]

A large stone has fallen down from my heart...

Cleaning restore points does solve the problem.
Drive C: looks like new.

Checking restore points before deleting with clean manager crashed rstrui.exe with read error at 0x00000000.
Second try out of register card of desktop icon crashed rundll.exe with read error at 0x0000001C and an unknown software exception at 0x7C953345.

I never noticed that restoring doesn't work, because I never came into the situation to need it.
May be this was the reason, that windows never deleted a restore point by itself, but collecting 4,5GB.

So there are left some questions for me:

1. Why windows doesn't add restore points data to size of drive? (When marking folders and files)
2. Where does windows store restore points data?
3. How to repair restore manager, not to get problems in future?

Taking a quick look into help file gave me no satisfying answer.
(Restoring rstrui.exe and rundll.exe doesn't solve problem as well)

Regards,
squareD