London Hop on Hop off bus?

I'll just have a go at your first question. Conventional wisdom at Heathrow is usually that you will be walking out the frosted doors into the rest of the airport with your luggage around 90 minutes from landing. That can be swayed though by long immigration queues. In the last few weeks some non EU citizens have been in a queue for Immigration / Passport Control / Border Control for up to 3 hours when the actual queue is usually 15 minutes or so. Also the Immigration officers are grumpy at the moment, for example they will be on strike again this Thursday. Once you surface into the rest of the airport figure 15 minutes to 30 minutes to get your bearings, use the toilet (finally!!), grab a bite if needed, get your Underground ticket / Travelcard / Oysercard and then just short of an hour on the actual Tube train, changing once.

There is an Original Bus Tour office in Victoria Station, and you can also buy tickets from an agent on the bus. I don't know about credit cards, I always use cash for these transactions. There are ATMs in Victoria Station if you need one. As I recall, I asked for and received a Rick Steves discount (this was a couple of years ago.) The boat is a tour, 1 ride. However, your hop-on-hop-off ticket gives you a nice discount if you want to purchase another boat trip, such as Hampton Court Palace or Greenwich.

Great, thank you both for the input. I have my fingers crossed on the status of Heathrow situation. Counting down the days.

Marty, you can purchase tickets on-line from the Original Bus Tour website at £23 per adult (instead of £26). You'll get vouchers that can be redeemed at one of their main departure points or at their main visitor center. Regarding the river cruise, the pass you receive for it with your ticket is collected the first time you get on the cruise, after that you just need to show your time stamped ticket to hop on and off within the 24 hour period. The time to get from Heathrow to your hotel can vary widely depending on how many planes are landing about the same time as yours, and how many gov't employees are manning the immigration desks. This past March when my husband and I went through Heathrow our plane landed about 10:15 AM, and we made it to Kings Cross Station via tube at 1:15 PM only because we knew how to navigate the airport and tube systems, and already had our Oyster cards.

You can also purchase bus tour tickets at the front desk of the Luna Simone hotel. I believe Original Tours is one of the ones they sell but can't be certain. Since that is where you are staying it might be more convenient for you. You didn't ask this, but I will throw this idea out to you: you might consider waiting until the second day to do the bus tour. That first day you will be tired and jet-lagged from the flight, and sitting on a bus may be likely to put you right to sleep. When I get off an international flight, the last thing I want to do is sit in another vehicle for a couple of hours. Perhaps walking in the fresh air the first day might be a better choice.