What is going on?

I own a 1999 chevy astro cargovan. On my way to work yesterday, it started running very rough like one of the plug wires came off. I pulled it off of the road and shut it off and let it sit for a few minutes. It started right up but the running rough still continues. I drove it straight home (about 5 miles) and parked it. I have checked the plugs in it and they are in great shape (just replaced about 2 months ago) as well as the wires and rotor and cap. I did a compression test on the front two cylinders and they both tested ok as well as a spark test on the plugs. They only thing I can see odd about it all is the spark from the plugs are shooting a sunset colored orange instead of a blue. It has a v6 4.3 I think. I am at a loss. Please help me