Software Deployment

I have been asked by a friend to help him update his users computers remotely, currently his organization is in the process of swithcing to a new system that will update these patches automatically for them.Unfortunatly they still have roughly 100-150 workstations that have not been patched since roughly last october.[:'(]
I am a programmer and I am familiar with C++,VB, Databases Etc. The Question I have is this, what is the best way to update these workstations that have not been installed with the new system yet? Previously they use to have a consulltant who would have used Winbatch which we no longer have. This script would then have run from the users logon sript.Problems I am having are How do I elevate the users privileges so that I can actually get the patches to install and then lower these privileges again. All users who logon to these workstations will have the lowest permissions possible <users on local machine>.
Patches that need to be installed are Service Pack 4 and all other microsoft critical updates after october.Can i use orca and modify these patches MSI and have the login script execute these MSI's?
They are running windows 2000 workstations off a windows NT4 Server and do not have SMS or SUS etc.Any Suggestions on how to apply these patches asap would be much appreciated. I know that if I can find the appropriate method of how to apply these I will get it to work just atm I am stumped as i am not sure of the technologies out thier that can do this.
Thanks for all the Help
Jerry