ISA can definitely do what you want and more. But ISA2006 has been replaced and the current solution is Forefront Threat Management Gateway. Both can be referenced <a href=”http://www.microsoft.com/forefront/edgesecurity/isaserver/en/us/”>here</a>
Another good source I recommend is <a href=”http://www.isaserver.org/”>ISAserver.org</a>.
Tom Shinder is aguably the foremost authority on ISA.