Windows 7 Ultimate; AVAST free.
Perplexed...When AVAST performs a full scan - typically once a week - it finds some processes that it identifies as threats. However, you can't select any of them - clicking the item does nothing - consequently you can do nothing with any of them !!
Do you happen to be running a custom scan and have elected to also scan memory ?
The reason I ask is you mention the word processes (avast normally uses this process term when it relates to memory) and the fact that you can't do anything with them; if it is a detection in memory, that isn't a physical file so can't be moved to the chest, etc.
Are you viewing these detections, in the results window 'directly on completion' of the scan (e.g. you haven't closed the scan) and not via the Scan Computer, Scan Logs (historic information) ?
So we will need more information on the detections, a screenshot of the results window would help.