Find Your Green
UNIQUES NOT ANTIQUES
To paint or not?
That is always the question.
The only rule thumb is if you want to keep your piece as a collector's item DO NOT paint it! It will decrease the value.
If you just want the piece for function and because you like the style (even if it was your grandmother's and your family never speaks to you again) - go ahead - have fun... there really is no wrong answer.
Just keep in mind do not put latex over oil, that will just make you cry. Oh, and don't use metal/ rust protection paint on wood... again, there will be tears.