I have driven a couple of times to Courmayeur ( in 2007 & 2008), and more recently to Switzerland ( twice ) and last year to Monaco.
The 'hardest' part of the trip is getting to Dover : due to our congested motorways and awful services!
Make sure you read all the stuff about driving abroad, and what you have to have in your car ( use the AA website which has a list etc). France has different requirements to Switzerland which is different to Italy...etc etc !!)
Get all the
stickers/headlight adjusters/breathalysers (!!)/warning triangles/high viz jackets etc online as certain high street shops ( sounds like halfrauds... ) charge a fortune for them.
My preferred route south from North East England is via Dover- Calais. I usually book a lunchtime ferry : try to book/pay for it well in advance to get a good deal. If you use the Dartford Crossing during the day, there is an electronic toll system ( it's free at night IIRC.)
You should register with the Dartford Crossing company online, then pre-pay before you travel. Otherwise you will get charged/ fined if you do not pay promptly as the cameras take your number plate details etc.
I also registered with SanF ( the French autoroute toll company: they have an office in Harrogate I think), so that you can buy a Transponder to stick on your windscreen and that picks up the tolls as you go through the automatic lane ( no need to stop as the barrier just lifts up ). You then get the total bill from SanF about a month later. These transponders make using the autoroutes so much easier, especially with a RHD car ! The price is the same as paying with cash at the Peages.
I tend to stay overnight in Reims, which is only about 3 hours from Calais. The Novatel is very good, plenty of parking and literally just off the Autoroute. It has a good restaurant as well.
The French autoroutes are great IMO, especially in Northern France where they are not too busy. Apparently they are getting more speed cameras now, but the last time I drove over there they were well signposted !
The French Aires ( rest stops) are very good, the larger ones have excellent facilities ( so much better than anything in the UK). They are clean, the restaurants ( and they deserve to be called that !) are very good: in fact you actually look forward to stopping for a meal ! They serve excellent fresh coffee, and the prices are OK ( Not like ours at all then !)
The fuel is expensive on the Autoroutes, and most of the pumps have credit card options. Also there is the option to fill up & then pull off the pump forecourt and park outside the shop to pay...most civilised !
As you travel further south the traffic builds up, in fact Lyon, being France's second city, gets very busy at any time of the day.
I have stayed overnight in Annecy en route to the Alps: that is a lovely city with canals and a lake, although I would not recommend a hotel in the city centre as the traffic is quite hectic !
I would try to avoid Geneva if possible, the traffic around there is very busy.
Anyway, I hope you enjoy your trip, you will find it so much more enjoyable than driving anywhere in the UK !!