Originally Posted by Thumper

I get to London once a year.

I would endorse Solly's. It is at the extreme of the locations of the jewish businesses, but a good eat and there are still plenty of stores to walk around. If you are interested in more variety, at the other end of Golders Green there is Chinese, Pizza, Hamburgers, Dairy Restaurants and so on. (also a short walk from the tram) As mentioned, GG should be a dinner destination, bu not much else.

Be prepared for sticker shock. If it is $1 in America, it is going to be a pound in London - very expensive town!

My wife and I have done the Big Red Bus, and again, I would highly recommend it due to the amount of time you have. You will get to at least see, if not go in, all the major London attractions. I especially loved the part where you get off the bus, get on a boat up the Thames, then get back on the bus. We bought our tickets via the internet before we left.
CHeck for dates and time of guard changing at the Palace, it is not every day.

Layovers like this are my favorite! Wife and I had a similar day like this in Zurich. Had such a good time, we tacked it on to our return from Israel the following year.

Have a great time, bu like I said, be prepared for sticker shock.