I am trying to setup a Linux box to replace my moms Windows XP box. Every couple months I have to come over and do work on it because the nieces/nephews/siblings get spyware and viruses. There isn't anything they can't do in Linux(except my moms Quicken but I think I may try MoneyDance out on her).

There will be four users on the system, two with admin rights(dad and I) and two with minimal rights(mom and brother). I would like to setup a guest user that has no password, this account will be very locked down and the home directory will not persist across reboots.

To help with adoption, I would like to get the user switching working out just as it works for them today in windows xp. Here is my best description of out it works in Windows XP for those that don't know.

1) On reboot the computer boots to the login screen.
2) Each user gets exactly one session.
3) When a user logs out, the computer goes to the login screen.
4) After a timeout it should kick the computer back to the login screen instead of a lock screen(not ending session).

I have tried setting up Kubuntu and it works ok for the first and second if everyone always logs out, meaning there is only one session. Me getting my nieces/nephews/mother logging out is just as likely as me getting a date with a super model. The problem is this, if I log in as say guest, then I switch user to say myself, then I log out it tries to put me in the guest session. I end up at a lock screen for the existing guest section.

The timeout to login screen also doesn't work the way I expect. Also it is possible to create multiple sessions if the users don't know what they are doing.

If anyone has suggestions or comments please provide them. I am not even sure if it is possible to accomplish the above.