92 Golf won't start

My daughter brought home her 92 Golf for me to fix her brakes. She had one more request, replace her CD player. The car ran great when I pulled it in the garage, but know it won't start. It's not firing. I get no spark from the spark plugs, from the wire from the coil to the distributer it's sparks a yellow spark once when the key is turned to the start position, but no sparking as the would be as it would be to fire the spark plugs. The only thing I can think of is when I was changing the radio out one of the hot wires sparked on some metal. I checked all of the fuses and they are fine. Tomorrow I am going to borrow a friends Haynes manual. I am thinking a relay or the hall sending unit on the distributer. The fuel pump does come on and hums while the car is being cranked over. Has anyone else had this problem or can someone point the direction. Dad has messed this up and the daughter all though is understanding just want's her car to run.

Thanks

Dave

Definitly the ignition switch! For those of you with only one car to get you all the way to the parts store as you turn the key to role over the engine wiggle the key innits socket. Sounds rediculous eh!, but guess what.....