try writing a query to the sysobjects sysusers sysprotects tables
you can see the definition of the protecttype in books online
just check out each of the tablenames in books online.
i also suggest if you go this way that you download a copy of systbl.chm from Here
it's very useful for debugging system table stuff and there are only a few mistakes in it.
(it says it's for 2000 but it's from 7.. syslogins is called sysxlogins in 2000)