I'm going to have Sensible World of Soccer 96/97 on my upright (when I finally build it in the next few years *sigh*), as even now it's still the best football game ever. I plugged my desktop machine into my bartop to test it out under emulation, and apart from the occasional instability in the emulator, it was a blast. Two player cabinet play would be even better.
Chaos Engine 2 and Speedball 2 are a couple of excellent 2-player games that you'd need to have.
If you have a trackball, then you could even play Lemmings - two trackballs would mean that you could play 2-player Lemmings, which only the Amiga version had, from memory.
A trackball would also also Worms - the Director's Cut - sheep on a rope, anybody?
Super Cars 2 wouldn't be too bad either.
Even though it's a shareware game and the graphics weren't exactly cutting edge for the time, Extreme Violence is great fun. Hell, it's been about the only game I've ever been able been able to convince my partner to play - she's not exactly computer game-friendly (but I am allowed to do whatever I want

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Extreme Violence is available here.