Thanks for all the information.
XP Pro is installed on the first 100 Gig partition of a 250 Gig Drive. Works fine.
Then I installed Windows 7 on the 2nd 100 Gig partition and it works fine, boot menu works fine also.
However, when I returned and booted to XP, it hangs when it reaches the desktop. Will not finish loading.
Deleted the Windows 7 partition, boot menu with choice of Windows 7 or XP remains and XP again starts booting and working normally.
Installed Windows 7 to a separate HDD. This added a 2nd instance of Windows 7 in the boot menu, Windows 7 boots fine but returns my XP to hanging at the desktop. Booted XP in safe mode, disabled all startup programs, retried with same result of hanging at the desktop. Remove the Windows 7 Drive and XP returns to normal.
Has me puzzled. Am I missing something simple? Sorry if I missed this in an earlier post.
Thanks for any suggestions.