Very strange booting issue


I was wondering if anyone encountered the same thing I did. I just did a
clean install of Vista ultimate, everything fine, then I decided to install
FSX, all with no problems. Then I created a second account so I could play
it without all the stuff loading up at startup like messenger, etc. It
played fine, but when I logged off to go back to my other main account, after
the password prompt, I get a black screen and a single instance of an
explorer windows open (opened to 'my documents' for some reason) no amount
of waiting gets me to explorer, I have to 'browse' from this windows to the
windows directory, click on the explorer icon and then, in second, explorer
loads and everything continues 'loading' as normal. Funnily, every time I
boot, after all this, I get Itunes loading up (I have an Iphone, so it sees
it and starts Itunes to sync it) Itunes acts as if it was the first time
running, with the little 'do you want itunes to manage your music?' window
and 'accept' 'decline' options, just at it does the first time you run it.
It was working fine before. Any ideas why this is happening? I don't
necessarily think it is Itunes, it just appears as if some elements of
shut-down are not registering, or this may be two separate issues, the blank
screen at boot up bothers me most.