We stayed at the Hilton Heathrow Terminal 4. Hotel is connected to Terminal 4 with a 6 to 7 minute walk from the terminal in a covered enclosed walk way.
You walk outside for a minute or less and then you are at the Hotel. Hotel provides a little trolley type vehicle if you need to use instead of walking.
The lobby, dining areas and bar are pleasant and welcoming. Executive Lounge is located on the 1st floor near the front desk. If you need to printed your boarding pass there is computer in the bar area. There is a cost for the internet. This is London and the cost is not cheap(GPB dollars). We had a weekend special so I don’t know how much breakfast is…it was included. Breakfast buffet was standard but good. Our room was clean and comfortable. The staff was very friendly and accommodating, especially Steven who sent up a birthday tray as I was celebrating my birthday. I thought this was a nice gesture and much appreciated… Now to get to London you can take the “Underground” from Terminal 4 to Piccadilly Circle. Use the elevator to -1 floor to get to the bottom level of terminal 4 (I think in front of Section D). Take the Piccadilly Line. We purchased a 3 day pass and if you don’t use all the money (one day) will be refunded. We were there for a weekend. The train takes about 45 minutes with stops. This is an inexpensive way to get to the center of London. In addition it you are staying at the Hilton Heathrow Terminal 5, there is a bus that picks up outside from this hotel to take you to Hilton Hotel Terminal 5.