After spending a few days in Melk, my wife and I plan to drive to Erding. it's over a 3hour drive which i don't relish. Is there any town or village of interest on or near this route where we could spend the night, thus cutting the journey into two trips?
What is your route? I usually recommend Burghausen. You will find the longest castle in the world there and a nice Altstadt along the Salzach River. I've taken family there during their visit from the USA. Stayed at the Hotel Burgblick years ago, and it has since been upgraded.
Another, rather underestimated option would be Schärding in upper Austria.
It’s a detour of about 15 minutes but worth it.
Or you take a different approach and go the longer route via Salzburg and spend a night there. Of course that would mean to find a hotel with reserved parking.
For the 2nd leg to Erding you could avoid the Autobahn but use country roads via Traunstein and Wasserburg am Inn to Erding.
Seebruck, on the north shore of lake Chiemsee, Seeon Monastery and Wasserburg am Inn would be worthwhile breaks on that route.