Avast Has 2 Folders. Safe to Remove One?

I recently uninstalled Avast 7 after I thought it was causing problems with a game (but it actually wasn’t). So I downloaded Avast 7 and re-installed it. I noticed that I now have to folders for Avast. One is here:

C:\Documents and Settings\All Users\Application Data\Alwil Software\Avast5

and the other one (which is the more recent i believe):

C:\Documents and Settings\All Users\Application Data\AVAST Software\Avast

Been using Avast since ver. 4 and never did a fresh install. Always updated within the program. It was only when I had to re-install Avast that I downloaded a fresh copy. Neither did I use the uninstall utility to remove all traces of Avast. Would it be safe to delete the one that is in C:\Documents and Settings\All Users\Application Data\Alwil Software\Avast5 ?

by delete i mean just clicking on the folder and pressing ‘delete’ ? or would it have leftover entries still in the registry?

Yes, you can delete “Alwil” folder, it was used by old avast 4.x/5.x.

thank you. ;D