This was an awesome series of games. I still play them on and off in Basilisk, a vintage Mac emulator. Like many games from that era, the Mac versions had much better graphics and sound than the DOS ones.
There is also a fanmade release called Oxyd Extra 2.0 that is designed for Windows. It only has 40 of the 400-odd levels from the original games, but it supports network play and has a separate set of co-op levels. I was playing it with my brother a few months ago.