Computer hang up after Boot time scan aborted accidentally

HI, I have been using avast for several years and am having some boot time problems. I scheduled a BT scan and my son aborted it. Since then I am having hanging problems and cannot do anything with my computer. I am running Win 7N 64bit. It is a new computer and has never had any other OS on it. Currently I am in safe mode with networking as this is the only way I am able to do anything. I have run a full scan with Avast and in the log there are archived files that I have no idea what they are, some look like Adobe reader, others i have no idea. It says they are password protected and are in the sandbox, but does not allow for any action (I don’t know if this is related or not) I ran MBAM and nothing was found. I am currently running Super antisypware and have only found tracking cookies so far. Do you have any suggestions? Thank you.

It is a new computer and has never had any other OS on it.
did it come with a preinstalled AV ? was it uninstalled before installing avast? was the vendors removal tool used to clear any leftover files that may conflict?
It says they are password protected and are in the sandbox, but does not allow for any action
avast will only take action on infected files

files that can not be scanned…reason given by avast…are just that, no more no less. it does not mean they are infected. this is just a scan error report

posting a screenshot will help us here