win98 sharing printer with win2000

I'm stumped, hope someone can help me.
Last year we switched from WinNT to Windows 2000 server.

Another person in the office, who has been using Win98
for years, set up her printer from her Win98 machine to
share to a Win2000 machine that she wants to use in tandem
with the 98. She is a member of the administrator group
in AD. She did not have rights on the 2000 to install
drivers for the shared printer, so I gave her local admin
rights on the Win2k machine. All went fine, until this
morning when she logged onto the Win98 machine with her
network password she has used for a month. When she
logged on apparently she got a message and her password
was updated (something like that, sorry, but she did not
pay any attention to the message).
After that, her desktop on the Win98 was totally
different. Not only was her wallpaper changed to the
Windows default, but her normal icons she had set up were
missing, and there were icons on the win98 of programs we
do use at the office, however they were very old programs
and programs that she never would have used. Also, her
internet and email had to be reset.

Sorry for the long post, but does anyone know what
happened, and how to avoid that from happening in the
future?
Thank you!
Vic