Vista - What do "Windows Update" and "system restore" have in common?

Problem:
Below problems happen together after an update from windows update. So far i
have not found out which. Reinstalling vista and both work again. Letting
windows update do the patches and both don't work anymore.

Problem 1 is Windows Update: it runs forever with a tranparent screen and
can only be stopped using the task manager.
Problem 2 is System Restore, which is able to create restore points (i can
verify this), but these created restore points cannot be accessed. Clicking
on the button gives a short visual "response" and does not list any restore
points. Clicking the button again and it states "System Restore is already
running".

Because both problems seem to happen together I am looking for a commonality.

Any suggestions?