network access

hello
On a school network we have some fixed PC's and wireless clients
windows XP and Vista
the fixed PC's can have both pupils, teachers or guests login to
them
the wireless are laptops and usually dont change user.
I want to assign 3 vlans students, teachers and guests
i need to have network access control depending on mac address and/or
who logs onto the fixed windows PC's, and be able to assgin the port
to the correct vlan
when the user logs of it should clear the port vlan so as to stop
anyone changing the PC and getting around the access controll
will 802.1X do this for me or does anyone have any other suggestions
network hardware is about to change to all cisco
many thanks