Unless you enabled auditing of logon events, you won't be able to retrieve that
information. XP Pro stores this information in the Security branch of Event
Viewer. Control Panel -> Administrative Tools -> Event Viewer is one way to
access it.
To enable auditing of future events, go to Control Panel Administrative Tools
and double click Local Security Policy. In the Local Security Policy Console
navigate to this location.
Security Settings -> Local Policies -> Audit Policy
In the right hand pane, right click on Audit logon events.
Check both the Success and Failure boxes.
Click OK.
That information is in the Security Event Log. Its been quite a while since
I logged into XP, I believe its: Control Panel > Administrative Tools >
Event Viewer. Select the Security log. There may be a lot of data in there
that you don't care about, you want to look for those with the event type of
'logon.'