Hello,
Went on this trip last November and stayed at the Park Inn by Radisson. There are free buses just down the road to the airport except I did not know that and had tickets for the Hopper bus which took me to the front door. We originally had an earlier flight which went later after lunch so we spent a long time at the airport. Luckily we had the lounge at Heathrow so we ate and drank there.
Had so much fun on this trip, enjoy :D
Jan