Why did moving the mouse cursor cause Windows 95 to run more quickly?

Interesting.

When I used to play computer games, back on Windows 95 or 98 (don't remember fully) I experienced a different weird behaviour. A lot of games would freeze at black screen and would remain there indefinitely until the CD-ROM was opened and closed - then the loading suddenly continued like nothing happened. For some games I had to repeat this 2 times to get them to start.

Wonder if this could have been caused by similar processes.