Resolved. Looks like this was a simple user profile issue. Using the local administrator profile to create the default solved the issue.
Ok, I have updated the BIOS on the Optiplex 790 to A11 and was able to get the Num lock to stay on during boot up. Now, it seems the num lock key will NOT stay set in the users profile. When a user logs onto the workstation we have to push the num lock key to turn it on each time. After the user logs off and back on again the num lock light on the keyboard goes off. The local administrator accound does not seem to have the issue, the numlock key does stay on for that account. The 790 is Windows XP SP3 fully patched. The registry settings for InitialKeyboardIndicators value in the registry is set to 2 per specifications. I have even tried changing the permissions of the folder for that registry key for the current user but that still does not work. I added a user before the workstation was joined to the domain and after the workstation is joined to the domain. In either case, the state of the num lock key will NOT be saved for either users in the local administrator policy or regular users. I have also tried alternate keyboards and that does not seem to help either. On the 780's and 755's Windows XP seems to behave properly. Anyone else noticing this type of behavior on Optiplex 790 that have Windows XP? Thanks again for the help.
Optiplex 790 num lock status not saving Windows XP