Problems with hotmail, I.E. 7 and Firefox

Since installing Internet Explorer 7 I've had a devil of a time, to wit:

1. Neither it nor Firefox 1.5.09 (which is my preferred browser)will open to my homepage, hotmail. When I manually go to hotmail it now always asks me for my password, even though I've told it to remember my email address and password.

2. I.E. 7 also only runs with add-ons disabled. When I go to "manage add-ons", everything is enabled on all the lists. If I then hit "ok", the program freezes up and I have to cntrl-alt-del to get out. (I've tried to post this query at the MS knowledge base forums but it won't let me!)

3. Firefox 1.5.09 also opens to a blank page and I have to go through the same stuff to get to hotmail. I should add that if I leave hotmail in either browser, when I hit the home icon to go back to it, I always have to re-enter my password then as well. Prior to installing I.E. 7 I never had to do that in either I.E. 6 or Firefox. I should add that earlier this week I dled and installed Firefox 2.0 but it kept crashing, so I went back to 1.5.

Someone at the Mozilla forum suggested I open Firefox in safe mode and reset everything, which I did. No help. They also recommended opening the Firefox applications folder and deleting the file called localstore.rdf. I did this too. No help.

Any suggestions greatly appreciated!
Balanchine