1997 Blazer electrical problems

This sounds like an intermittent bad ground or almost broken ground wire causing the current to find ground thru other circuits. If you are going to tackle this yourself you will need the wiring diagram otherwise find a local electrical shop. You might try gently moving wire bundles around to see if you can reproduce the problem and give you somewhere to focus your search. It all comes down to how much your time is worth.

Sounds like flood damage. Have you had it since new?

Now that you mention that, the 97 I had did have a door switch problem. (Drivers side). The part of the switch that stuck out was bent. Work around was to tape switch closed till I replaced it.