Problem with Mafia install

[shellbell]

I installed a store-purchased Mafia game and ran just fine. Then, system froze when trying to launch game. Ended with task manager. This seemed to run havoc on user profile which had to be recreated and reinstalled from backup. Now, Mafia game could not be played or uninstalled, got message to log on as adminstrator with rights to write to the registry. My user accounts have administrator rights and even tried logging on as administrator. Thought maybe the disks were bad, so exchanged at store for new ones. No difference. Tried a last ditch effort of just deleting the files. Still getting the same message when I try to install game. I have tried disabling anti-virus in startup. I am not having problems installing other games. Sent the game manufacturer tech support email over a week ago with no response.

System Info:
Windows XP Pro ver 2002 Service Pack 1
AMD Athlon XP 1600+
1.41GHz
256MB RAM

I appreciate any help.

Thanks.