Which password are you talking about?  Windows?  Or the system set up?

 

To boot into safemode, I tap F8 when you see the Dell splash screen.

Leave it blank.  If that does not work, then you changed it, ot spyware did and only a clean install will fix that, unless you are real techy.

dexterdoo

 

Dell uses Sysprep to preinstall Windows on a  computer. Sysprep sets a password other than the default blank. So either this is your problem or you have forgotten the password you set.

 

I don`t know if your situation here, but if you can still access XP, try this if you think it is a Syprep problem

XP PRO
Bypass the password requirement
Start/Control Panel/Administrative Tools/Local Security Policy/Local Policies
Security Settings/User Rights Assignments/SecurityOptions
In the right hand pane "Recovery Console: Allow automatic administrator logon"  change this to “Enable” (Right click/Properties)

 

XP HOME
Start/Run/Regedit
Navigate to
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Setup\RecoveryConsole
Click Recovery Console
Security Level in right hand pane.  Right click/Modify
Set the security Level to 1
Remember to back up the key before changing it. (Right click Recovery Console/Export.  Give it a name you will remember and save to the hard drive)
 
OR
2. To set the Administrator password to a known term go to Start/Run, type
control userpasswords2
and click OK. 
On the dialog that opens Under Password for Administrator click "Reset password." 
On the screen that opens enter the new password desired in the appropriate block and again in the block to confirm the entry. 
(If the "Reset password" button is grayed out, check the entry at the top "Users must enter a user name and password to use this computer.") 
Click OK,
then Apply. 

To set the password to the null (blank) value simply leave both password blocks blank.

Let's get back ot basics here.  Is the original poster totally locked out of the machine?  If not and all you want to do is change the Built -In Admin password go to:

 

Control Panel>Admin Tools>Computer Management>Local users & Groups

 

Right click the Admin Account and select change password.