Couple of ways to do the registry edit.

You can use the reg delete command in a batch file.
reg delete HKEY_CURRENT_USER\Software\Sysinternals\BGInfo /f

You could also export the registry key that you want to delete to create a registry file. Then edit the registry file by putting a hyphen in front of the registry path but inside the brackets.

Windows Registry Editor Version 5.00

[-HKEY_CURRENT_USER\Software\Sysinternals\BGInfo]

Then to delete the key you could put this code in your batch file.
regedit.exe /s someregfile.reg

As far as rebooting the computer that is easy enough using the shutdown cmd.
shutdown -r -f

 

Use this website to help you find the commands you'll need:

http://ss64.com/nt/

And the following commands:

SCHTASKS

DEL

SHUTDOWN /r

 

Before Techshopguy asks why it doesn't work, XP Home does not include the Schtasks.exe command line tool, you have to use the GUI.
Control Panel | Performance and Maintenance | Scheduled Tasks
or
Start | All Programs | Accessories | System Tools | Scheduled Tasks

 

Before Techshopguy asks why it doesn't work, XP Home does not include the Schtasks.exe command line tool, you have to use the GUI.
Control Panel | Performance and Maintenance | Scheduled Tasks
or
Start | All Programs | Accessories | System Tools | Scheduled Tasks

Another of the many reasons to get Pro instead of Home...

 

Thanks all. Very helpful and in depth. I am going to try some of those options and I will post and let you know how it worked.
Got to love people making work machines with XP Home!

 

Solution works, just created a batch file to do the delete and force restart. Thanks! Just wanted to know if there were any ways to make this happen automatically every 28 days?

 

Control Panel | Performance and Maintenance | Scheduled Tasks
or
Start | All Programs | Accessories | System Tools | Scheduled Tasks

How To Schedule Tasks in Windows XP