Ancient battery most likely, which also means cruddy connections, not only on the battery, but also on the starter itself.

Now, back to your real issue- you are saying the truck won't start easily when it's stone-cold? It takes a bunch of cranking to get it to fire off? But once it's running, it works as designed all day, until it gets stone-cold again?

Could be fuel filter/pump related. But more likely the air idle motor on the back of the throttle body. this seems to be a fairly common problem on these late 90's Dodges. My 97 Dakota is included in that mix.

It's an easy fix, right on top of the engine, and the part is cheap.

But a 5 year old battery? NO way I'd be going into winter with one that old!