Puzzling! A few more questions - which version of IE are you using? (Right click the file iexplore.exe you found and look at properties/version). You may wish to view
this from MS which appears to refer to IE up to 5.5
I assume you have an IE icon when you click on the 'Start' button? What happens when you right click on that icon? I get three menu options:-
Browse the internet
Internet properties
Remove from list - not the path to the programme.
Internet properties allows me to set IE as default.
Are you familiar with regedit? If not, PM me and we'll have a look at your registry in private.
Which Firefox also? I have V2, and when I go to 'Firefox/Tools/Options' I get a few tabs which include 'Main'. You say you do not see this?