I have to agree with Merry. I stayed at the Heathrow Hilton in a day room a couple of years back - the BA flight was scheduled to arrive at 4:45am, and we weren't excited about heading off to London that early.
It is a 5 - 6 minute walk from the terminal - but it is an enclosed walkway and there are luggage carts available at both ends. It is a short and free trip on the Heathrow Express to the other terminals.
My only folly was not listening to my wife and neglecting to grab a luggage cart - I can still hear myself saying it is a short walk to the hotel, why bother?
[This message has been edited by Larrude (edited 05-23-2000).]