Terminal server and citrix are good answers to allowing "industry standard" programs to exist side by side with other systems.
We have Citrix at the school I work at. I have connected to the system and used the standard windows desktop with RISC OS (3.1 and above) Mac OS 7 and above, Windows 3.1 and above, DOS and Windows CE. It is also possible to connect with Linux, OS/2 and Nokia Comminicators. Getting microsoft off the desktop and only into the server room is a huge saving on time, both maintainence and start up. It also means high energy processors don't need to be used in the classroom, cutting noise and heat.