Win XP Professional altered after Microsoft updates

I installed some Microsoft updates recently and had the computer just the way
I wanted. After I shut off so the updates could install and then turned it
back on, once it came up, everything had changed. I could no longer go to the
classic view (even though I selected the option), all my program settings had
disappeared completely, including what files they had used. (Example, my
version of Quicken completely lost its file. Fortunately, I had it backed up.
My settings in Firefox and Internet Explorer had disappeared as well,
including the bookmarks and the page I had set for home.)

I want to be able to go to Classic View--and hope this won't happen every
time I install updates!

Sorry that this is repeated under another listing. Took a little bit to
figure out how these discussion groups worked.