"So it means that it might actually be nothing serious just miscommunication between windows and avast at start up? It is not something I need to worried about and there is nothing wrong with avast?"
Yeap you are right! Nothing to worry about.
No it's fine some people may be new at this and it doesn't matter if it sounds stupid. Asking questions is very appreciated whether is a good or stupid question... people always want to make sure
"if I instead of uninstalling avast I choose to update the program through avast is it a good idea? Because I think if it didn't uninstall properly other issue might arise".
Having the latest version of avast is always the best and it solves previous known issues that users faced. When I upgraded my avast 8 to avast 2014 all the issues that i faced including the miscommunication between windows and avast at start up it was all gone. Plus you get all the cool new features of avast 2014 with far more better protection. It also fixes other issues that many users faced and reported.
By the way upgrading from avast 8 to avast 2014. Follow this: Uninstall avast 8 via add/remove. Restart your computer. Download this tool and run it in safe mode
http://www.avast.com/it-it/uninstall-utility. Restart your computer. Download and install avast 2014.