IIS can be replaced by apache web server. All you need is a
localhost server right? 
Yup, it is better to uninstall your winXP before Microsoft detects
its repeated serial number.
If you really deleting WinXP, all the settings in the registry will
gone with it, so no point keeping those software, it can't work
either.
So, since there are backups, reinstalling everything again is the
safest. 
