web browser Q:The links! They do nothing!

My SO is having strange connectivity problems in Mozilla Firefox. At random times, all of her links and bookmarks will simply stop working. When she clicks on a link, the browser appears to think about it for a second (gives the “loading” animated cursor) and then just stops–no error message, no “unable to find server”, no change in the screen, nothing. Sometimes the problem fixes itself and sometimes it requires a restart to fix it.

We have a wireless network at home, and at first we thought it was some radio interference or something, but the signal strength meter shows that she’s getting a signal, and her IM program will continue to send a recieve as normal when this happens. We’ve run spybot, ad aware, etc., and I’ve checked the computer question sticky thread, all to no avail.

Has anyone seen this before?

Are you using a pop-up blocker, and do the links go to pop-up windows?

No. It’s not just some links, it’s everything–Yahoo! news stories, Amazon, the works–not just pop-ups.