Learn Farsi: رقص را دوست دارم.

In Farsi, when you express a general preference or love for something, that concept is treated as a definite whole. Because you are talking about "dance" as a complete category, it takes the definite direct object marker را.

Is رقص a noun or a verb here?

It is a noun meaning "dance." When talking about hobbies or interests, Farsi speakers often prefer using the noun form (like رقص) rather than the infinitive verb (like رقصیدن, meaning "to dance").

How is this different from saying دوست دارم برقصم?

دوست دارم برقصم uses the subjunctive verb and means "I like to dance" (focusing on you performing the action). The sentence رقص را دوست دارم translates closer to "I like dance" or "I like dancing," focusing on the activity or art form itself.