Last time I wandered the campus (2003 alum here, Southern Miss to the top!) the library PC's were Windows w/ Deep Freeze for lockdown/control. The big computer lab at the front of the library was a 90/10 mix of Dell/Apple.
The Fine Arts lab in Mannoni PAC was 100% Apple. The CS Lab on the 2nd floor of the Chain Technology Building (TEC) was dualboot Win/Linux. The Engineering lab on 2nd floor TEC was Windows and so was the SET lab on the 3rd floor.
The Psych building lab was also Windows.
When I started as a freshman, you could still dial into ocean to get a shell for e-mail or negotiate PPP @ 14.4kbit. It was a sad day when they removed everyone's shell access, but at least they left scp access with an scp client.
I do still have my orca account though!