I did this all week long when I was there last month.
Of the 4 offered planet hollywood has the best one.
There's a free shuttle to/from the Rio
From the TR board:
RIO LAS VEGAS - SHUTTLE TO THE STRIP
Q. Is there a shuttle that goes from the Rio Las Vegas Hotel to the Strip?
A. The Rio and our sister properties, Bally's/Paris and Harrah's Las Vegas on the Strip, offer a complimentary shuttle to and from the Rio. Please note: the shuttle only runs from the Rio to Bally's/Paris or Harrah's Las Vegas, not from Bally's/Paris to Harrah's Las Vegas or vice versa. The shuttle runs daily from 10am to 1am. Pick-up times are approximately every 30 minutes from each location (depending on traffic conditions).
Pick-Up Locations:
Rio: Carnival World Buffet entrance
Bally's: Race and Sports Book entrance (side of Flamingo Rd)
Harrah's Las Vegas: Shuttle/Bus/Trolley drop off