Basically, neither the mouse or the keyboard are responsive in game. When starting The Settlers Two, in the MS-DOS command line it says "Unknown Mouse Interrupt".

I've had this problem twice whilst trying to play two of my favourite old games - Fifa 2000 (Not from here) and The Settlers 2 (From here). I'm running Windows XP using a Generic Microsoft Optical Mouse with a USB plug which has been plugged into a PS2 adapter. My keyboard is just a normal keyboard that came with the computer plugged into the normal socket.

Could someone please suggest something? It's ruining my potential enjoyment of two great games.

Windows XP is probably the problem here. Did you try DOSBox?

Yes, and The Settlers runs horribly slow. Even with 1800 CPU cycles (My maximum).

1800 cycles!!! My usual to run games is 10000!

I guess you have an extremely slow computer? I would recommend a 1000mhz computer to run DOSBox.

Oh, I was mistaken, my fastest is several tens of thousands revolutions but it's still running very choppily.

Does increasing the cycles get your mouse and/or your keyboard more responsive?

I'd like to know so I can know right on if another person come asking me the same question. While it would be nice to be the answer, I somehow don't think it might be it.

Well, there seems to be an optimum speed for my mouse between 3000~6000, anything higher than that and my moving the mouse around becomes jerky.