Taiwan or Shanghai? Which place did you enjoy more?

For those of you who have travelled to both, which did you enjoy more?

For context: i'm travelling for 1 week with a family of 5, 2 of them are elderly and im torn between either Shanghai or Taiwan. I'm primarily looking for a place that has

-good food

-sight seeing (temples, some nature, etc)

-attractions that are easily accessible/easy to get to especially for elderly folks

-less stressful