There are a lot of ports to this game, linux, win, macos, even dreamcast. Checked the linux and windows ports, quite stable (but I'd suggest often quicksaves - some places hang the game once in a while), the resolution can be changed to 800x600 (and in one version even more). http://www.icculus.org/rott/
(sorry for a doublepost, but this comment is also important here)