heathrow hotel...

You could stay AT the airport, at the Yotel in Heathrow. There's nothing more convenient than that, for sure. www.yotel.com

A lot of the hotels at Heathrow offer loss leader rates and make up for it with exhorbitant prices for food and drink at the hotel, especially the more isolated hotels commonly used by Priceline where you have little choice other than the hotel.
Rates are also a lot cheaper at the weekend, epecially 4 stars who depend a lot on conference trade which vanishes at weekend.
The best budget deal is probably the Travelodges (Central for Terminals 1,2,3 and Terminal 5 for Terminal 5) if you can get a 19/26 GBP rate (<$40) which are quite common here from the Travelodge UK website. The cafe's here won't rip you off.
Failing that the Premier Inn (Bath Road) is probably the best of the no frills 3 stars - but not the M4/J4 site which is isolated.

As you probably know there are no free transfer shuttles at Heathrow, the Hoppa Buses cost 4 GBP each way and for many buses you can get public buses.

I've stayed at Heathrow Lodge on Old Bath Road. I think I paid 40-45 GBP two years ago; they had a free shuttle to the airport (the earliest shuttle was 6 am). They don't have a restaurant but there are two pubs nearby. I took an early shuttle to Heathrow and ate breakfast there while waiting for my flight. I reached the lodge by taking a train to Slough and catching a bus from there.

We stayed at the Jurys Inn Heathrow and were very impressed with it. It seems new. It's very clean and unbelievably quiet. It's right under a flight path, and I don't know how they can block the noise that completely! Not luxurious, but everything one would need -- and close to the airport. We ate dinner there and also thought the food was good. Their prices on weekend nights are very hard to beat. Very clean.

We also stayed at the Jury Inn and found it very acceptable. We had dinner there and paid a fair price. Large, efficient, no problems. I believe we used their shuttle service to return to the airport that morning, if I recall correctly. We booked online before leaving home for our last night in the UK and it was all fine.

We also stayed at the Jury Inn. It was a nice hotel and the dinner was a buffet, which was a decent price. There was no shuttle. We took the Hoppa bus, at 5:30 AM which was free, I think, to the airport the next morning. At least, I do not remember paying. It was early and I might have forgotten. If you look here there is a discussion on Hoppa Bus and free local bus: http://www.londontoolkit.com/lhr/hotel_hoppa_bus.htm

I might have taken the free bus and not known it. Jury Inn is on the free route, according to the posting above.