ccipups

We'll be arriving via United at 10:50, on July 30 and departing on Kenya Airways at 20:00. So arriving at T1 (UAL's moving in June) and departing from T4. We haven't determined whether we'll do carry-on or check through.
Any suggestions for a short trip outside the airport? A friend has suggested Windsor Castle or choosing one or two specific places in London.
I've read some previous posts on this topic and 9 hours seems like it would be enough time to see a bit of something besides the airport.
If a late arrival leaves us with less than 8 hours, how about some suggestions for decent restaurants in the airport or at aiport hotels? We'd probably get a Yotel cabin or try to get a reservation at one of the lounges.
I'm looking forward to reading all your opinions.

Odin

For lunch options outside the airport area, there is the Ostrich pub in a nice village called Colnbrook, just beyond T5.

http://www.theostrichcolnbrook.co.uk/

Or in Hounslow town itself, there is a great Indian restaurant recently opened called Mantra.

http://www.mantradining.com/

It's rather posh for Hounslow. They are not open every day for lunch.

Windsor and Staines are good options also if you have the time.

TimS

You will have time for a quick trip to London if you wish. Buy a one-day, zone 1-6, off-peak travelcard for £7.00 at Heathrow. It will get you to London and back on the Tube and cover all Tube and bus rides in the city. Allow one hour each way. Take the Piccadilly Line from Heathrow to Hammersmith, walk a few feet to the other side of the plaform, and take the District Line to Westminster. You'll be right by Parliament and Westminster Abbey. Start walking toward Trafalgar Square or anywhere else you choose.

Windsor Castle would be another obvious choice. It's a 15-minute taxi ride or a 30-minute local bus ride from Heathrow.

yk

In case you will have some lugguage w/you, Heathrow airport does have left luggage services at each terminal. Go to heathrow's website and search for left luggage.

You should have enough time for Windsor castle. There are buses from the Heathrow Central bus station that goes to Windsor.

Of cousre, you'll have to account for the 1+ hr to go thru immigration/customs when you arrive, and time to check-in/go thru security for your Kenya Airways flight.

ccipups

Thank you all. That was just the kind of information I was looking for.
Any other thoughts or suggestions?

Odin

Bus from Heathrow Central to Hampton Court Palace, lunch locally. Takes about 50mins on route 111.