AVG Antivirus just rendered my computer useless

AVG Protection
4

Hello Stefanie,
We regret for the inconvenience caused. Please try to reboot your PC in safe mode using the instructions on the article http://avgclick.me/rebootintosafemode and check whether you could login to your PC.
Thank you.

1

Just installed AVG antivirus.  First it slowed my computer down and rendered Firefox useless.  I restarted my computer and it won't allow me past the login screen!  Help, this is a 1 year old Windows 10 computer with a lot of important info on it.

3
I am unable to login to safe mode.  None of the options listed works. 
2
Hello Stefanie,
We regret for the inconvenience caused. Please try to reboot your PC in safe mode using the instructions on the article http://avgclick.me/rebootintosafemode and check whether you could login to your PC.
Thank you.