I need help big time. Someone (IE) stole Firefox.

This is a strange situation.
Maybe you can help.
For the last 2 weeks, funny things have been happening to this machine.
I have(had) Firefox as my browser. I've had 2 weeks worth of problems with Hotmail. I always sign out of that account when finished. It always signed me out. Now, it brings me to MSN.com. The word continue would appear after I signed out. Sometimes it took me directly to MSN.com. I X'ed out of that and would continue with the open Firefox browser. It was also my home page.

Today I cannot, no matter what I have tried, sign into Firefox. It will not open.
I certainly thought Internet Explorer was disabled. It is now the browser. What happened to Firefox?
I have tried system restore...nothing. Cleaned up as much as I know how to do. Still no Firefox.

What could be happening?

Two weeks ago my grandchildren were visiting and on the computer. Could they have done something that would have started this sequence of events?
Should I un-install Firefox and then re-install it?
I can't explain it better.
This is an HP machine running Windows XP.
Thanks for any suggestions.

And see if it makes a difference.


1. Open Control Panel

2. Open Add or Remove Programs
(be patient, it may take a little while for this window to load properly)

3. On the left hand side, click on Set Program Access and Defaults (bottom option)

4. Click on the little set of downwards arrows to the right of 'Custom'

5. The top option is: 'Choose a default Web Browser'. Click the button for Mozilla Firefox
(At this stage you can chose whether or not to tick the box for IE 'Enable Access to this program'. I'd suggest you try it both ways)

6. Try to start Firefox.