Okay, I know this thread is pretty old now (well, 3 months almost). Anyway, I finally found the answer. (then it took me a few minutes to track down this thread, cause I couldn't remember the subject)
1: Shut down your browser completely (it must not be running when you do this!).
2: Open up C

Program Files\Netscape\Users\[your profile]\prefs.js in your favorite text editor (like notepad, ultraedit, arachnophilia) (on my box I put del instead of [your profile])
3: Scroll down to the very bottom of this file and add the following line, make sure (!) that you hit the [Enter] key after typing this line in;
user_pref("mailnews.start_page.enabled", false);
4: Save the file, close your editor, and re-fire your browser. Check your mail. The netcenter page should not load at all now
Or, you could do the following as well. Follow steps 1 and 2 as above, and step three almost all the way through. Instead of adding that line at the bottom of the page, add this one instead (again, make sure to hit [Enter] after the line)
user_pref("mailnews.start_page.url", "http://www.futurequest.net/"

;
Then continue with Step 4. When you check your mail, FutureQuest will show up in the bottom frame. Now, if you prefer to see FQuest in a real browser window, you could put in a different URL instead. Just make absolutely sure there are quotes around it and it's spelled correctly
Del