What follows is hopefully a useful summary of things to do while visiting London. I've included tips on how to get the most out of each thing, together with a link to more information. While you're there be sure to try a pint (or two) of Wadworth 6X. Have a wonderful trip!!
The British Museum
Well worth a visit, even if you're not really a 'museum' person. Inside this sprawling, beautiful building you'll find all kinds of incredible treasures including Cleopatra's mummy, the Rosetta Stone, the Elgin Marbles (the front of the Acropolis that my forefathers generously removed from the front and took home with them, never to be returned), and much more. Free entry, though donation is encouraged. Special exhibits cost money.
NATIONAL GALLERY/NATIONAL PORTRAIT GALLERY
Lots of stunning and priceless paintings from across the ages. Located off Trafalgar Square you can't go wrong with any of these. Amazing buildings, stunning art (much of it HUGE), and it's all free (donation suggested).
TOWER OF LONDON
This is one you just should not miss. You could spend an entire half day here quite happily, and I would highly recommend it. Built in the time of William the Conqueror a thousand years ago, and then added to and altered over the ages, it's an incredible piece of history. You can see the Tower's guards, known as "Beefeaters", the fabled ravens who live in the castle (legend says that when the ravens leave, England will fall), the crown jewels, and visit Traitor's Gate where the heads of enemies were displayed on spikes for all to see. Definitely go. And have something from Paul's patisserie afterwards as you stand by the river to look at Tower Bridge.
If you want a nice beer and a bit of pub food right in the middle of the West End, you can't go wrong with the Salisbury. Food including the fish and chips, and any of the meat pies, are fab. For beers, try Timothy Taylor's Landlord. Once you've enjoyed your first pint, have another.
Right off Soho Square you'll find a little gem of a pub called The Toucan. You don't have to like Guinness to visit here, but it helps. They have two small bars, one upstairs, one downstairs. Neither are particularly fancy, but that doesn't stop this being an incredibly popular spot. The reason is this is simply the best pint of Guinness outside Dublin. Most of the pumps on the bar are for either Guinness or Guinness Extra Cold. And if you're in the mood they also have an excellent selection of Irish whiskey. In the summer you'll find people out on the pavement drinking Guinness in the sunshine. Downstairs all the bar stools look like pints of Guinness. A fun place. One I used to drink in regularly with my mates when I lived in England.
Lamb and Flag
While we're on pubs, we might as well do the Lamb and Flag next. You'll find it down a small lane half way between Leicester Square and Covent Garden. Its nickname used to be The Bucket of Blood, earned because the alley outside was the location of many bare-knuckle fights in the early 19th century. Good beers and decent pub eats, off the beaten path.
Everyone should at least visit the Harrod's food halls. It's beautiful inside and has the most amazing collection of food you've seen in your life. If you have the energy to venture beyond the food hall, be sure to visit a variety of departments where you'll find interesting surprises on what those with money choose to spend it on. Gold-plated taps in the bathroom shop, and an interesting array of animals in the pet shop.
The very first department store in the world, and one of the greatest. This is a HUGE store on multiple levels. It's located at 400 Oxford Street, near the Bond Street tube station. Lots of great clothes. Buy something to get yourself one of their distinctive yellow carrier bags. Definitely worth a visit if you're looking for a cool new item of clothing you can say "Oh this old thing, I got it in London last time I was there" when somebody remarks on it.
The Red Fort
For a great curry in the heart of Soho look no further than the Red Fort. You'll find it located on Dean street. Apparently Bruce Willis, Matt Damon, and Tom Cruise have all eaten here. Chicken Tikka Masala yum yum.
Hutong and the Shard
Hutong is a very nice Chinese restaurant on the 33rd floor of the new Shard building, located on the south side of the Thames river near to Tower Bridge and the Tower of London. It's worth going just for the views out of the floor-to-ceiling windows. But the food is pretty good too, as is the decor inside the place. Book ahead. Way ahead.
St Katharine's Dock
St Katharine's Dock is an old converted marina with shops, bars and restaurants. It's located just off the River Thames, not far from Tower Bridge. A good place to grab a bite and watch the boats come and go and for general people-watching.
The London Eye
It's the number one tourist destination in London. And for good reason. It's a lot of fun, and gives you a tremendous view over the city of London. Built in 1999 to celebrate the Millennium. Takes about 30 minutes to go around. You can see Big Ben, St Paul's Cathedral, Westminster Abbey, and Buckingham Palace from up there. It's really good to do at the beginning of your trip so you can get a lay of the land as you view London from 440 feet in the air. Book in advance. Tickets are cheaper that way, and your wait to get on it will be much shorter.