just happened-cannot close windows

[compdoc]

> I also have firefox open, cannot close it, no icons on either in the upper
right corner.

Definitely a crash. As to troubleshooting, might be info in the logs. I've
seen hard drives crash an OS like that when a bad sector develops. These
show as 'reallocated sectors' in SMART.

Make sure the PC's cooling fans work, including cpu and gpu fans. 

Hopefully someone sees your message in time to try helping while it's still
in that state...