Reset all virus checks?

I have COMODO on a just installed Windows Vista Home Basic.
Service packs 1 and 2 cant install with virus check on and these packs are
straight from microsoft download not a cd?
With virus check on pack 1 has 20 problems, pack 2 has 3 problems, and comodo
seems to be fixing these on the fly?
How do I reset the virus rules?
If I turn virus off then packs install but can I now run a virus check or will it find
problems in the packs?

When these packs are straight from Microsoft then those are more than likely false positives.

The behaviour you are describing, automatically quarantining threats, only happens when the Real Time scanner is set to “Automatically quarantine found threats during scanning”. When disabling that and telling it to add to the exclusions you shouldn’t have a problem.