Vista - Offline Files "Change Limits" button not working. Cannot change Offline Files Settings

My Offline Files has been doing some strange things lately. Not only does my
computer lock up to 100% CPU usage every 2 minutes for 1 minute at a time
due to the CSCService (Offline Files), but the "Change Limits" button under
the Disk Usage tab in the Offline Files control panel does not not work.
When I click on "Change Limits", nothing happens.

If I click on the "Delete Temporary Files..." button, a status bar appears
and stays on screen. I clicked this button and left the house for more than
5 hours and came back and it was still on the progress indicator.

In the control panel, it shows 99 GB in use and 99 GB available (???) in the
overview. I have 250GB HD so not sure why it's showing I have 99GB
available. And under Temporary offline files, it shows 99 GB in use and 99
GB available. It's like my offline files has become corrupt somehow.

This is the 2nd time I've had to re-install Vista due to problems like this.
I really need to keep offline files enabled, but it just doesn't seem to
work and/or causes my computer to crap out.

Does anyone know how to repair/reset the Offline Files so I can change the
limits in the Control Panel again???