1993 dodge 350 key does nothing

[landscaperdude]

93 dodge 1 ton 4wd. after sitting for 8 days unused in rainy weather, it now wont start. The "wait to start" light and others on dash don't come on. with key in run position, the only thing that works is the windows(dome and headlights work, and don't dim when working windows). turn signals don't work. really, nothing happens when key is turned. do I change the obvious ignition switch, or is there anything else to check first. never gave hint of a problem before.

[Chris Stewart]

I'd do some basics, clean the battery connections and check the battery ground at the engine block.
How many volts on the battery?