>> I don't know if I can boot XP Home in safe mode <<
The generic procedure is quite simple. Start (restart) PC. After the POST screen and before the windows splash screen repeatedly press the F8 key.
Note If you have multiboot option, you should select the windows XP first, press Enter and after that press F8.
On the windows options menu, press the down arrow keys and select Safe Mode. Now you should see (you have windows XP Home Edition) at least two accounts. Click the one named Administrator. Type the administrator password, and then press ENTER (try first a blank password). After the password acknowledgement, click Yes to confirm that windows is running in Safe mode.
>> how will I know of it is disabled in the registry? <<
You will never know if you don?t' have the rights to view/modify the registry, so you should learn how-to solve the above problem first.
Finally, I'd have some suggestions.
1. After someone has give you some advisese, try as many as possible tests and give as many as results. For example, you didn't tell which your actual account's right is.
Suppose that your normal account has administartor rights. In this case, try again to goto command prompt (via Start, Run, type cmd and press Enter. Type the following command:
Note Don't forget to type the /scannow parameter.
If it doesn't work once again you should check for viruses / spyware using the latest definitions.
2. In addition, give more info:
2.1 Do you have the windows XP CD ? If so, what is printed on the hologram ? (you should look for a text as: oem, retail, recovery disc, etc.)
2.2 Was / Is Office installed and what is its version ?
Trying to unweave, unwind, unravel
And piece together the past and the future,
T. S. Eliot