Wife started car to let it warm before leaving for work. When she went to the garage, she smelled an electrical burning smell. Said there were no heater fan or radio. Backed out of garage,and said it was idling rough. She shut it off, and now everything lights up on dash, but nothing when you turn the key. No click, nothing. Won't start with jump either. Anyone have any ideas?

 

The electrical burning smell should have been a big hint
A wire or few have rubbed up against something which shorted out the wires
May be near some exhaust pipes
Anyway, check the wire bundles and move things around a little to see if that changes anything
If it does then you're on the right track.
If you have a multi meter (volt meter) and schematics then try looking for the five volt reference line.
Sometimes it gets shorted out and it cranks but won't start
If it doesn't crank then look at the starting system on the schematics and find the starter relay (check out youtube videos on how to check starter relays)
This should give you enough ideas on where to search or how to search for the problem

Good luck

 

Maybe the Ignition Switch. My 01 Ford Escape happened 10pm on the highway while driving home.