The two timeouts are fixed. 5 Minutes for user and 1 hour for installer. There is no difference in the access currently provided at level 2 & 3, note level 1 by default has blank password and therefore auto logs in. Level 1 provides access to the soft controls on the home page, if you set a level 1 password then you have to enter it to get the soft buttons and it times out after 5 minutes.
Level 2 & Level 3 enable webbrick reconfiguration. There may be versions in the future where Level 3 allows reconfiguration of more items.