admin screens only works completely in Opera

In the last few days, I’m suddenly having problems loading my WordPress admin screens.

In IE 6.0, the admin screens don’t load at all (“The page you are looking for is currently unavailable.,”) while in Firefox (1.5) the pages will load, but only partly – huge elements of the pages, and many function buttons, aren’t showing up on most admin pages. In Opera (7.54), everything loads correctly.

Here’s an image showing the same page in Firefox and Opera, so people can see the sort of thing I’m talking about.

I love Firefox, and don’t like having to use a different browser. If anyone has any suggestions, I’d very much appreciate hearing them. Thanks.