Dentists use a personal preference. As for the ones you mentioned, I can tell you what they are for:
- Christmas tree: I usually use the Arkansas stone (white tip) for molding or polishing resin material.
- football: these are usually diamonds, and I use them to make occlusal discount for preps on the crown or cut into keys.
- flame: used to trim the smooth edges of teeth. I use fine-grained sand to complete the burr.
- round: small to cut retention features, large to mine cavities (slow).
That's what I do with them. As I mentioned, every dentist has a different preference.
Hope this can help!?
