Hi there
If you want you useraccounts to have administrators privileges on your workstations, then they can do anything.
If you want your users to shraed te same desktop and applkications settings then you can have them to share the same user profile.
There are ways to do this in a domain environment (roaming profiles / mandatory profiles) but I don't know if that can be done without a domain.
Try look at an application like this -
http://www.research-lab.com/userprofilemirrorread.htm.
This might be helpful in this case.
Regards
Mikkel