I'm not sure why a network problem would cause such issues with your print spooler subsystem but I don't know why your network packed up in the first place.
If you have Windows XP, then doing a repair installation should not lose any of your data. It is likely to put on the original Windows XP files though, so you'll probably have to re-apply any Windows service packs and updates.
For this reason, using System Restore should be quicker and easier if you know of a restore point that reflects a time when everything was OK. Windows XP isn't my thing I'm afraid but I'm sure that someone in the Windows XP board on D-A-L.com can advise you better about System Restore if you need help with it.
Also, you specifically referred to NTDLL.DLL in your original post. You might want to see if you can retrieve a fresh copy of that file from the Windows CD. In Windows 98, there was a utility called System File Checker (go to Start Menu > Run > type
sfc) that could extract an individual file if you had problems with it but I don't know if this exists in Windows XP.
Let us know how you get on