What's the best way to manage my inexpensive, but good, red wines after
opening the bottle, but not drinking it completely?

Do I recork it and keep it at room temp for a few days?
Do I recork it and keep it in the refrigerator for a few days? A week to 10
days?

I don't want to drink a whole bottle just to have a glass with dinner, but I
don't want to throw out 3 fifths of a bottle either.