The amount of available disk space on my machine decreases every time I run a game - what should I do?
Disabling System Restore for any drive which you do not back up regularly is not recommended.
There are several causes for this condition which this article will not cover:
If you notice that 50 - 100 MB of available hard disk space is being used every time you start a game, you may need to disable System Restore for the drive which is storing your game files.
For more information, please see the Microsoft Knowledgebase article for the System Restore feature.