I would opt to get off the M25 by 7 am as it starts to get busy then. Though I would think that Heathers advice is best.

I love the ferry. It gives you a break from driving, and a chance to grab a half decent hotdog.

Not the fastest route though.

So the girlfriend called an audible and I ended up having to go anti-clockwise! Thanks for everybody's advice though.

Need some more help now please!!

Gotta be at LGW for 1800 on November 4th. But prior to that would like to visit a ski boot fitter in Fulham. Hate driving in town and thinking parking will be a nightmare. Is there a way to park in the vicinity of LGW for not mega bucks (and safely/securely) and get into town and back out in a day for again, not mega bucks? Or am I just gonna have to park in town?

I assume that LGW is the airport code for Gatwick. In which case 1800 is a really bad time to be on the motorway. It will be full of commuters going home, I would opt for the Gatwick Express if that is the case. Then no need to drive to LGW at all.

+1 I'd take the Express.

Ok, obviously haven't given you enough information.

I'm driving from Cornwall to collect her. Then taking us both to Derby afterwards.

I will also have my entire life (including skis and this desktop PC) in the car. So not keen on leaving it unattended for great amounts of time in places I don't know...

I'm assuming the Express no longer makes sense?

Could you do the ski boot fitting another time.It also avoids exposing yourself to the car getting broken into in London. Get a train or bus from Derby to Fulham might be a lot less stressful than driving in London. Also I do not know where the congestion zone starts out that direction.

If you can avoid Fulham and are going to Gatwick airport, then I would suggest missing the M25 completely at that time of day. I would get as far up the country via motorway then go cross country to get to the airport, by 1800. Or you could aim for the M27 then do the A27, A24 A264 and then M23 up to the airport. That route is mainly dual carriage way. Returning to Derby might be a lot easier as by the time you have finished at the airport you will be going against the traffic.