I have firefox as my default browser but...?

Some software requires Internet Explorer specifically, not just "a browser". For example, Microsoft's own Windows Update facility requires Internet Explorer and won't work in Firefox. Unfortunately it's just a fact of life that even if you try to be very conscientious, you may not be able to avoid using IE in some situations.

To fix your Internet Explorer, try these suggestions:

1. Run both a virus scanner and a spyware checker on your system. Some sort of malware may be interfering with Internet Explorer, which is not uncommon (targetting IE is one of the most popular ways to attack your computer).

2. If you have IE 6 or below, upgrade it to version 7.0. Go to www.microsoft.com/ie and download the installer. You can download the installer with Firefox. This may fix it by completely upgrading it.

The error itself may provide some insight as to what is going on. It's a good idea to write such errors down, as well as what you did immediately before it, and at what point it occurred (eg: just after I clicked Save, just before I clicked Print), as this will help diagnose the issue.

Removing the Internet Explorer icon won't uninstall it. That icon just launches it. It is heavily integrated into the operating system, and really can't be gotten rid of. (The Department of Justice had this very argument with Microsoft.)

Firefox has a setting called "Always check to see if Firefox is the default browser". Make sure it's turned on. Also, go into Add/Remove Programs. There's another icon in there called "Set Program Access and Defaults". This lets you choose which programs are your default browser, etc. You can also make Internet Explorer hide itself. However you can't completely get rid of it. If you do all this and IE still launches sometimes, it's because some program or service is specifically calling on IE, rather than "a browser". There's not much you can do about that.