Question : Monitoring and limiting internet use

I have a client that would like to be able to monitor and with the "flick of a switch"/"click of a button" disable internet access for given users.  Will ISA server allow this?  The requirements, in order or priority:

1.  Identify which client systems are using the current bandwidth.
2.  "turn off" the client's internet access
3.  Easily Managed (They are not COMPLETE computer novices, but they don't have any REAL expertise on staff either).
4.  Actually "view" or "see" what the users are accessing (Haven't actually asked for this but I know the company's practices well enough to know this something they will ask for if 1 and 2 can be done.

Note: This CAN be a device, but more likely/preferred would be a solution that would be installed on a Windows (SBS) server that acted as a router.

Answer : Monitoring and limiting internet use

If they are novice than ISA probably isn't the way to go.

Webmarshal isn't a bad product.