The media player issue is worse than we knew.
Streaming video from CTV, CBC and CNN all fail when run in Firefox because they require Windows Media Player. When I install WMP 9 (the latest version for Win2K) the machine crashes when the media player plugin launches. I find no fix for this. There are alternate players and I will investigate them, but they have not, in the past, been a complete success.
As far as the above sites go, the problem is that the pages with embedded players do not allow the user to choose a player. The BBC does, and as long as you choose Real Player everything is fine (WMP crashes as described above).

Possible solutions:
1) install alternate media players and hope for the best
2) tell instructors that they can't use CBC, CTV or CNN in their classes (cost = $0)
3) upgrade the labs to Windows XP (cost is $127 per machine = about $6100)

So far I have spent most of the last two days on this (and related) problem(s).