From the West End the M40 is usually the better start: out through Oxfordshire and Warwickshire, onto the M42 around the south of Birmingham, then north on the M6. It is the more pleasant road and the more predictable one, and on a good day it is quicker.
From the City, from north London or from anywhere near the A1 the M1 makes more sense: up through Northamptonshire and Leicestershire to Catthorpe, where it meets the M6. The M1 is the faster road in theory and the more temperamental one in practice, with long managed-motorway stretches that can drop to fifty miles an hour for reasons nobody on board will ever discover.
Both routes converge on the M6 around Birmingham, which is where the journey is won or lost. The toll motorway that bypasses the worst of it is sometimes worth taking and sometimes not, and a chauffeur who drives this several times a month knows the difference between a queue that will clear and one that will not. Beyond Stoke the road opens up and the last hour is straightforward.
We usually plan one stop. Four hours is a long time to sit, and five minutes somewhere civilised is better than arriving stiff. If you would rather run it straight through, say so.