We used to stay at a different hotel every time we went to London until we came across the Covent Garden Hotel in Monmouth Street. It is a superbly decorated hotel in a very convenient part of London and answers the OP's list of requirements pretty well except for the view. Each room is decorated in a unique way with a lot of taste, the staff are the nicest I've encountered in any hotel in the world, and there is a pretty good restaurant with one of the best afternoon teas in London (it can be seen in Woody Allen's latest movie, Match Point).

LOL... Will keep that in mind next time I take my elephant to London .

rfrost hit the nail on the head IMHO. There isn't the "perfect" London hotel. There will always be a problem with a hotel/hotel room because we each have our own definition of what is good and what is not.

Just my 2 pennies ...

I found both the Lanesborough and Dorchester to be disappointing with the latter amongst the most disappointing luxury hotel I have stayed at in the world . The Savoy (pre-Fairmont) was resting on its laurels and Claridges was imperious.

I think One Aldwych is as perfect as it gets. In Covent Garden in the Aldwych, excellent and unpretentious service, outstanding Concierge desk and fitness centre with pool with underwater music.... I think the Four Seasons Canary Wharf comes second.

Oddly, no one has mentioned the Mandarin-Oriental Hyde Park... I am not a "fan" of this place; their top management is arrogant and lacking.

Sofitel St James

Cracking little hotel, just 3 minutes walk from Piccadilly. Gets great reviews on tripadvisor and you can get great rates at the weekend (�100 a night via priceline)

Very very very comfy beds!

I second luxury's vote on One Aldwych, I go to London just to spend a night here and take a dip in the pool! The rooms a lovely, the food is excellent, service most efficient and the pool is just fab. I loved the champagne and strawberries I got as a welcome during my last stay (and I just have an ordinary room).

The Amex Centurion 2 for 1 promotion usually leads me to try and then return to Mandarin hotels (NYC, Miami) again and again, but this one is not in that group. I only stay here once a year when I'm in London for a two night stay to maximize the benefit. Not that it is a poor hotel...I've actually had some very nice stays from time to time. The facilities are just too dated in many areas (the bathrooms come to mind).

Another vote for One Aldwych, my favorite London hotel!

My favorites in no particular order, I love them all for different reasons are:

The Atheneaum on Picadilly
The Ritz on Picadilly
Mandarin Hyde Park
Renaissance Chancery Court - This is the quietest London Hotel ever
The Langham (formerly Langham Hilton)
The Goring - Like staying at a friend home. Very quiet also
Threadneedles (in the City)
Marriot West India Quay (Canary Wharf)

All have excellent service, rooms and great concierges....
Will be back in London in March and staying at Canary Wharf again. I love the City and Canary Wharf though most tourists find them a bit off the tourist track.

I much prefer the FS at CW. Nicer rooms, much more pleasant public spaces, way better service. I only use the Marriott if the FS is full. Being at CW is just too convenient sometimes.

Great restaurant too.

Well honestly it depends what you are looking for. I travel to London on average of 30 to 60 times a year and there are only two hotels I will stay at there. The Lanesborough and The Dorchester. I personally love the Lanesborough as I know almost all of the staff there and are close friends with them. And also because of the very personalized service. No matter whether you stayed with them 10 years ago or last week, almost everyone there remembers you. Plus the rooms are absolutely amazing and always very comfortable. Oh and the internet, all premium movies, and basically everything where it is extra in other hotels such as The Connaught.

Then there is The Dorchester. An absolutely gorgeous hotel, right on Park Lane. It has been there for 75 years and is basically a landmark. The service is amazing, rooms are very comfortable. BUT, it's the most expensive hotel in London. Nothing is free with them. You have to pay for internet and movie usage. The beds are very comfortable though. One thing I don't like though, it's not really for someone whose on vacation, unless you like having to dress up in a suit and tie or blazer and pants to eat breakfast. It's very formal, but old world English style.

Oh and forgot to mention that The Lanesborough uses VI-Spring beds. They start at $8,000 (US) for a queen. And they are absolutely the most incredibly comfortable beds I have ever slept in. And the pillows there are huge oversized pillows.

When we were in London last year - we stayed at the Marriott Park Lane - right at the Hyde Park tube station. It is a very interesting property - especially for Marriott. A boutique hotel. It is perhaps a notch below true luxury status - and the rooms are somewhat on the small side - but I thought it was a really nice property in an excellent location. Robyn

One Aldwych is superb. If we're mentioning Dorchester and Lanesborough in the same breath, though, I don't think the OP would consider the rooms of decent size, and the view is rather different!

DITTO! Of course the restaurant is wonderful and the pub grub in the American bar is excellent too, as are the teas. They have had a recent change of management (Terry Holmes has retired and Stuart Proctor has moved up to be chief, seamelss of course. They have purchased the building across the yard from the Carriage House and will add more suites and a gym.
I cannot imagine spending a night in London in any other place! It is my home away from home, unless I am cruising on Seabourn, of course.

Jane in PHL (headed to the Stafford next month)

I like both the Connaught and the Covent Garden. The staffs at both are fantastic. Friendly and helpful all the time. The Covent Garden is more modern. The locations are both great. Covent Garden in the heart of that area and Connaught in Mayfair with a easy walk to places like Selfridges or over to Bond Street.