There is a very new virus out called w32.bugbear It is ranked 2nd right now next to klex.h If you have not patched your IE 5.X in the past 18 months their is a chance you have gotten it. The symptoms noted on symantecs sight directly corelate to your. Here is an excerpt:
Security Response has seen that because the worm does not properly handle the network resource types, it may flood shared printer resources, which causes them to print garbage or disrupt their normal functionality.
Here is a link to the article(remove all spaces after pasting to your browser bar)
http://securityresponse.symantec.com/avcenter/venc/data/w32.bugbear@mm.html
There is a removal tool and instructions. The instructions are pretty straight forward. We got this virus today and removed it promptly, I advise you do the same.
Good Luck,
SLM