Would one person be able to login to, say, "Account A" and another person login to "Account B"?
No, unless you have a Microsoft Terminal Server (service) running. In this case you will be able to switch between existing already running sessions using the "Terminal sessions" icon on the Full Control mode window toolbar.
By profiles you mean Windows accounts on the remote PC, correct?
With Remote Utilities you always connect to the current Windows session. If no Windows session has been started yet, then you connect to the Windows welcome screen from whence you can then log in as a Windows user, just like you would do if you were sitting in front of the remote PC.