Oh, rose geranium sounds lovely! Mmmmm....
I cannot decide which is my favorite for either question.

In the past couple days, I have used tea tree, lavender, and Roman chamomile for several issues. I usually use lavender, peppermint, and eucalyptus radiata the most, though (therapeutically).
The citrus scents are probably my favorite just to smell. I have lemon, sweet orange, and pink grapefruit. MMMmmmmmmmmm........