Which is exactly why New York subway platforms are such miserable pools of hell. Although, once you get on the train, it’s nice. I don’t know which system is better.
That sounds like a good itinerary to me. If you go to the V&A it might be worth taking half an hour or and hour to visit either the Science of Natural History Museums too - they are literally a two minute walk from the V&A and each other. They’re about a twenty minute walk or so from Harrods, too.
Oh, one small tip: check on the internet before you leave for the station, especially at the weekends, because there is a LOT of upgrade work being done at the moment and some lines are completely closed at weekends. There are also rail strikes planned, though mostly not in your area of London. TFL and National Rail are pretty good about updating their websites, though, so it’s easy enough to check.
If you’re coming in from Slough, btw, you might as well buy a paper travelcard rather than use Oyster, since you’ll need a ticket from Slough anyway.
As others have said, forget the changing of the guard at Buckingham Palace. It comes off as a band concert in front of a really big post office. Horse Guards parade is another thing entirely and well worth seeing. Huge well groomed horses, troopers all shined up and in bad weather wearing big blue and/or red riding cloaks. Also, if you are lucky go across to the nearby park and watch the Life Guards and Blues exercise and drill. Since the IRS set off a bomb some years (decades?) ago the household cavalry may not drill in the park any more.
Hampton Court is a delight. It beats the Tower all hollow. You can get there by tube train and bus for one reasonable price.
Transportation — if you can’t get there by tube or rail you don’t want to go there. Anything outside London proper can be conveniently reached by rail. Anything in London can be quickly reached by tube. In addition, rail is a great way to see the countryside.
I can’t agree with the disparagement of the London Eye, the big glass Ferris wheel. Once is enough but everyone should do it once.
Do not try to walk the embankment without a compass. The river is tidal and you can’t figure out what way you are going by looking at the water flow – half the time the river is running up stream.
Avoid hotel restaurants. The only time we walked out of a restaurant after looking at the menu was in a hotel on Liecester Square. Way over priced.
Travel to many locations outside of London but within a reasonable distance of it are now more commonly done by bus (or, as they say, by coach) than by train. I discovered this in 2003 when I was arranging in a SDMB thread for a Dopefest in London during my trip to the U.K. back then. I mentioned that I would take the train from Oxford to London. Someone here told me not to take the train but to take the bus. There are two competing bus companies doing that route. They offer cheaper fares and they run more often. This is different from my experiences when I lived in England from 1987 to 1990.
I actually kind of enjoyed the London Dungeon, FWIW. Tacky yes, but also Macabrely fascinating in it’s own way. And little pipes run around the ceiling to drip slime down the walls, which I thought was a nice touch.
Only the Queen is called ‘Ma’am’
There is no extra charge for visiting the Crown Jewels. Nor would there have been one in the mid-1990s.