Computer not booting into Safe Mode (or at all currently)

I was attempting to remove avast software with their removal tool. In order to do this, it is recommended you go into safe mode. For some reason I have not been able to enter safe mode using the typical method so I selected for Windows to boot into safe mode upon restart in the system configuration tool. I feel like that was a mistake as after I restart I only get a blank screen. My computer is on and running, but nothing comes up at all. I can't seem to boot in at all, and I can't toggle the option off in system configuration because I can't get there. Does anyone know a relatively painless solution to this problem? Any help would be greatly appreciated. Thanks.

Submitted November 30, 2017 at 11:33PM by machinich_phylum http://ift.tt/2iuIaZg