Tom...are you considering table service restaurants or thinking just counter service? Two reasonably priced table service restaurants that we enjoy are the Plaza at MK and Kona Cafe at the Poly. We haven't been there for some years but it sounds like Trail's End at Fort Wilderness is still very good and reasonably priced. I believe it is still a buffet. Ohana at the Poly is all you can eat for around $21 if you enjoy lots of meat . We've not eaten there but recommended it to friends who loved it and lots of people on these boards seem to enjoy it.
I'm not sure that I would call any WDW restaurant a budget restaraunt. (Of course that depends on where you live now and what you usually pay. )
We ate lunch one day at the Land food court. (Specifially pasta and potato area) We were both very surprised how good it was. Either that or we were very hungry!