The options in general:
1. System restore from command prompt (http://pcsupport.about.com/od/fixtheproblem/ht/systemrestorecp.htm tells how).
2. Repair install from the Windows XP install CD
3. Clean install form the Windows XP CD.
If even the 'safe mode with command prompt' option doesn't work (your post seems to say so), find your XP disk and start with the repair, as told in http://pcsupport.about.com/od/operatingsystems/ss/instxprepair1.htm
Kees
xp will not open and stays in a loop of options that do not work

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