General error mounting file system

[Eric]

I get that error when I boot up. The message continues by saying it will 
terminate the shell and try again. I've gotten this message before and 
the computer usually boots fine although there are times when I try to 
boot that it never loads past the Kububtu progress bar. The drive light 
is on, showing activity but it won't load.

Any idea what the problem is or what the solution is?

TIA.

Eric