Yes, but very proper English. Not a lot of people use whom anymore. They would just say "She's going to meet the person she talked to on the phone".

No, it's not right - there's an important preposition missing. You talk TO a person, so you have to include the word 'to' in this sentence. Here are some possibilities: "She is going to meet the one to whom she talked on the phone" - very awkward and unnatural "She is going to meet the one whom she talked to on the phone" - a strange mix of formal and informal "She is going to meet the one who she talked to on the phone" - a bit more natural "She is going to meet the one she talked to the phone" - natural (inserting 'to' but omitting the relative pronoun) "She is going to meet the person she talked to on the phone" - most natural of all. This is what a native speaker would say.

Hi! I think you should add 'with' before whom. "She is going to meet the one(or the person) with whom she talked on the phone."