1. Any major/minor bugs
Depends on your definition of "bug".

Last program update affected members running older AMD processors.
2. Best version to use
I would download 3.13 amnd do a clean install.
3. Should I uninstall avast home and zonealarm
This is entirely up to you, but if you are going to install CIS, you would need to remove ZoneAlarm, at a bare minimum (2 firewalls is a recipe for disaster). Uninstall using a thorough uininstall tool like Revo Uninstaller.
4. Is CIS any better now than 1/2 years ago
IMHO, yes, but many would argue it's the same.
Ewen :-)
My system: xp home sp3
1 gigibyte ram
IE7
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