clean up apps like that generally cause more problems than they solve with windows 7.
To answer your question it's them you should be asking. Programs like that require a lot of specific information for each version of windows to even hope to work right. You vista copy shouldn't be used with win 7 even if you could get it to work. This is actually a good thing for the moment.
Best route is to find out if they ever updated pc-doctor to work with win 7.
I know system mechanic finally did but it took them a long time. (similar program)