Whenever I try to launch Quake II, whether I run it in safe mode or not, the screen the game is displayed on is the size of a postage stamp. Any ideas as to what to do to remedy this?

Yamagi.

Yamagi is a source port for Quake II. It updates the game's engine allowing it to run on modern hardware with better compatibility. You still need the original game, it just replaces the rendering engine.