XP has no general "win98 mode". It is possible to run specific programs in
a win98 compatible mode. But, normally one only applies that option to a
game executeable file. I shudder to consider what would happen, if one
applied a compatibility mode to a part of XP iteslf, or to a vital program
like internet explorer.
Unless she can recall exactly what she did, and then undo it, and if you
have no restore point, then I suggest thinking about a "repair" installation
of XP. For this you will need a real XP CD, not a PC-maker's restoration
CD. If you have a real XP CD, then read the following:
http://support.microsoft.com/default.aspx?scid=kb;en-us;315341
http://www.webtree.ca/windowsxp/repair_xp.htm
http://www.extremetech.com/print_article/0,3998,a=23979,00.asp
Note that a "repair" installation of XP does not fix most registry-based
problems. If you have one of those, then a full re-install may be required.
If all you have is a PC-maker's restoration CD, save all personal fles
(e.g., DOC, JPG, etc) off the PC. Get an external USB hard drive, if you
need a large place to quickly store the files. Then run the restoration
program and in a few minutes your PC will be back to the day you bought it.
Once you fix the immdiate problem, consider doing one or more of the
following:
1. Turn system restore on.
2. Use the Microsoft program Ntbackup.exe to save a copy of the entire
documents and settings area. This contains most of the XP registry and
other key settings.
3. Get a good third-party disk imaging program and occassional make an
image. Norton GHOST is the classic program of this type, but I prefer a
newer one called Acronis True Image.
4. Downgrading you wife's user account to "limited" instead of
"administrator".