Posted 08/18/2009 at 04:18:49pm

The ability to uninstall the .net Framework assistant was actually provided by a hotfix to the framework.   MS moved it from being added at the computer level, to a per-user level.

How to remove the .NET Framework Assistant for Firefox

http://support.microsoft.com/kb/963707 

Posted 06/30/2009 at 08:42:28am

I can vouch that it's not Vista blocking the loopback recording.  I've had to go through the very painful experience of converting my own Webex recordings from their proprietary format back to a standard avi format (The newer Webex supplied .wmv conversion tools produce garbage, or fail completely).  
After a lot of research, it appears that this capability is disabled on purpose.  If you subscribe to conspiracy theories, RIAA/MPAA has asked computer manufacturers to disable this feature.  (Lenovo does this, among others).  Enforcement used to be purely done by customized drivers (hackable), but on some notebooks it's also disabled in hardware (hacked drivers=blue screen).
There is a software solution, but you need to ensure that computer isn't disturbed by other I/O demands.  If disturbed you will get pops and skips.  VMWare isn't real-time enough to keep up for extended periods.
 It's also not free, but Virtual Audio Cable does simulate a sound card enabling you to connect a "virtual" cable between the real sound card's output channel and the virtual card's input.  It's a bit confusing to setup, but the trial mode is sufficient to prove it's functioning.
http://software.muzychenko.net/eng/vac.html
To my knowledge, Sound Blaster cards all still have this capability enabled.  One of the few compelling reasons to consider an addon sound card over the built-in ones.