avast Free Not starting with Windows 7

Over the last few days this has been happening. When I start my system, a message flashes up that avast is unable to start. Usually after a reboot, this goes away. However I don’t think even that should be necessary. But in the 2 days even that does not work. I have tried to start it manually in services, and I have tried a repair. Nothing is working.

And since this problem has started, it seems to crash Firefox as well. So 2 questions.

The first, obviously, is would a complete uninstall/re install fix this issue. Also, I have a dual boot system with XP Pro running with Avast, on another partition. Would that have an affect on the Windows 7 partition/boot?

Any help would be appreciated. BTW, both systems have the latest version of avast with the new definitions.