From the airport
Train: C1 to Atocha, then C5 to Alcorcon Central, then metro L12 to Parque Oeste. It's a 1hour 22 minutes trip. If you are in the city for a few days buy a T-10, Multi-person card for 10 journeys, (€12,20). It works on the bus too.
Taxi: It's a 20-30 minutes trip and is around €30.
Aerobus shuttle: Drops off at Atocha, Cibeles (night) and O'Donell-Doctor Esquerdo to Airport T1,T2 and T4 and costs €5.
When you arrive at Barajas Airport, you can take metro line 8 to Nuevos Ministerios and change there to line 10. At the Puerta del Sur Station change to line 12 and continue to the Parque Oeste Station. The Hotel is a 10 minute walk from there. In total it will take you about 90 minutes.