I'm traveling with my daughter 17 years of age. Would like to see the most in 2 days. What beach would you recommend for a day? And what/where would you reommend for a show a night. Is it better to go see a show in Habana or in Varadero?

Varadero Tropicana is cheaper than Havana and on the same theme, Club Pariesienne at the Hotel National is a smaller scale, cheaper but good, I recommend it in Havana, Havana itself is worth the trip, next time you should stay outside of Havana at the Playa de Este for the beach and you are close to Havana for the sights and action.
Depending on which Varadero hotel you are in, most have a decent show, there is a outside bar by the Sunbeach Hotel that has a small late night show after the others are done.