Restricting software installation

There are several software packages on the market that you can use to limit access to the system. Also depending on the O/S you can create a user account to limit the use of the system.

Here is an answer if you are using win2000. Secify if you use another one:
Dfault security settings for Windows 2000 can be described by summarizing the permissions granted to four default groups (Administrators, Power Users, Users, and Backup Operators)and three special groups.
Users group provides the most secure environment in which to run programs. On a NTFS volume, the default security settings on a newly installed system (but not on an upgraded system) are designed to prevent members ofthis group from compromising the integrity of the operating system and installed programs. Users cannot modify system-wide registry settings, operating system files, or program files. Users can shut down workstations, but not servers. Users can create local groups, but can manage only the local groups that they created. They can run certified Windows 2000 programs that have been installed or deployed by administrators. Users have full control over all of their own data files and their own portion of the registry.
Users cannot install programs that can be run by other Users. They also cannot access other Users' private data or desktop settings.
To secure a Windows 2000 system, an administrator should:
Make sure that end users are members of the Users group only.
Deploy programs that members of the Users group can run successfully.
Users will not be able to run most programs written for previous versions of Windows because older Windows either did not support file system and registry security (Windows 95 and Windows 98) or shipped with lax default security settings (Windows NT). If Users have problems running legacy applications on newly installed NTFS systems, then do one of the following:
Install new versions of the applications that are certified for Windows 2000.
Move end users from the Users group into the Power Users group.
Decrease the default security permissions for the Users group.

The answer is for win2k:
Default security settings for Windows can be described by summarizing the permissions granted to four default groups (Administrators, Power Users, Users, and Backup Operators)and three special groups.
Users group provides the most secure environment in which to run programs. On a NTFS volume, the default security settings on a newly installed system (but not on an upgraded system) are designed to prevent members of this group from compromising the integrity of the operating system and installed programs. Users cannot modify system-wide registry settings, operating system files, or program files. Users can shut down workstations, but not servers. Users can create local groups, but can manage only the local groups that they created. They can run certified Windows 2000 programs that have been installed or deployed by administrators. Users have full control over all of their own data files and their own portion of the registry.
Users cannot install programs that can be run by other Users. They also cannot access other Users' private data or desktop settings.
To secure a Windows 2000 system, an administrator should:
Make sure that end users are members of the Users group only.
Deploy programs that members of the Users group can run successfully.
Users will not be able to run most programs written for previous versions of Windows because older Windows either did not support file system and registry security (Windows 95 and Windows 98) or shipped with lax default security settings (Windows NT). If Users have problems running legacy applications on newly installed NTFS systems, then do one of the following:
Install new versions of the applications that are certified for Windows 2000.
Move end users from the Users group into the Power Users group.
Decrease the default security permissions for the Users group.

There is software out there called DEEPFREEZE
that takes care of that. You can download and install software but as soon as you reboot, it is gone. I have tried it and so far it works great. Your user can even delete essential files and as soon as he reboots, the files are back.
I had a prob with users downloading chat programs and I eliminated it with deepfreeze.
They can use the download as long as they don't reboot..after that, it is gone.
You as admin can control what gets placed on theputer by disabling deepfreeze and adding whatever you want.
This also helps if users delete programs and the associated shared files that go with them, simply reboot and the system is restored...
good luck!

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