This is London made legible in one private, unhurried window: a door-to-door vehicle, a local English-speaking driver and a route that can favour the landmarks you care about rather than a fixed group itinerary. Start and finish at a centrally located hotel, B&B or apartment, then use the two hours for a quick visual orientation, a handful of photographs, or a more personal sequence of pauses.
Big Ben and Westminster, Buckingham Palace, the Royal Albert Hall, St Paul’s Cathedral and the London Eye are useful suggested anchors, not a compulsory checklist. Choose a few, ask to pass another, or change the order around traffic, weather, event closures and your own interests. The ride is deliberately short, so it works best as a clear introduction rather than a promise to enter every landmark.