Best way to travel London, Scotland, Wales

We tend to use the word "rail" to apply only to trains between cities. For instance, a direct train between London and Edinburgh takes about 5 hours. Each city has its own local transport - Tube, bus, and river boats in London; bus and one tram line in Edinburgh; St. Andrews is pretty small and walkable. Do you have a guidebook covering your destinations?

In London we will be doing the typical and planning on using public transportation.

We would like to see, if possible, York Minister, Glastonbury, Wells Cathedral, Baths, Edinburgh Castle, St. Andrews and Loch Ness.

The guidebook is on its way.

"I am thinking rail to tour around London"
In London, you will use the tube (underground/subway), bus, taxi, river boats, and walking to get around.
The tube is easy to use. Just pick up a tube map once you are in London.
Likewise, the bus is a good way to get around. Pick up a bus map at some tube stations.
The river boats are a good way to travel and to get a good look at London from a different viewpoint.

"then rent a car to see Scotland and Wales"
Yes. You can easily get to Edinburgh on the train from London.
Once you are in Edinburgh, you do not need a car to see the sights in Edinburgh.
You just walk around. Once you are ready to leave Edinburgh, you can take a train to Glasgow or other destinations.

For destinations out in the countryside, pick up a car in Edinburgh.

Some destinations in Wales can be reached by train. You would have to tell us where you wish to go before we can tell you whether you need a car to reach them.

You really need the Great Britain guidebook by Rick Steves.
This will pay for itself many times over in helping you plan your trip.
I can tell you are in the beginning stages in the planning of your trip.

Jas, we were posting at the same time.
That is great that you have a guide book on its way.

"We would like to see, if possible, York Minister, Glastonbury, Wells Cathedral, Baths, Edinburgh Castle, St. Andrews and Loch Ness."

York Minster--you will pass right by it on the way from London to Edinburgh on the train. York is a wonderful stopover.
You will want to spend two nights there, and one entire day seeing its sights. Then train out on the morning after the second night.

Glastonbury, Wells Cathedral--pick up a car to go here. Both are in Somerset; beautiful countryside.

Bath--easy train ride from London.

Edinburgh Castle--easily reached by train.
St. Andrews and Loch Ness--rent a car to go out to these.

You are beginning to set a pattern of cathedral cities/towns--York Minister, Glastonbury, Wells Cathedral, Bath.

If seeing cathedrals is of great interest to you, I suggest you look at a visit to Salisbury Cathedral.
It is magnificent, and you can see their own original copy of the Magna Carta there.
Salisbury is not too far from Bath.

From your original question:
"Rail all the way, rail in London car to Scotland, or even rail in London, fly to Scotland?"

--"Rail all the way from London to Edinburgh"--yes, with a stopover in York roughly halfway (but not quite).

--"Car to Scotland"--No. If you are wondering about driving from London to Edinburgh, you would be exhausted, and it would take far more time than the quick and relaxing rail journey.

--"Fly to Scotland"--No. York is almost half way (but not quite) from London to Edinburgh. By the time you take the train to York from London, I would not bother flying the rest of the way. The train trip from York to Ed. is fast and the scenery out the train window is great. Sit on the east side of the train going north.
However, York has an airport, and you could fly to Edinburgh if that is what you really wish to do.

I think that the first thing you should do is take a look at the British Rail Route Map- click link & select 3rd one down.http://www.nationalrail.co.uk/stations_destinations/maps.aspx

TRAIN: > Consider going London (Kings Cross) > York (overnight). Then York > Edinburgh (2 nights?). Now, if you wish to go into scenic Scotland, you could take a coach tour from Edinburgh or train to say Perth & then hire a car. (The best bits in my opinion are out in the north-west > driving through the highlands to the Isle of Skye. Loch Ness is very big but not that scenic - well, by Scottish standards).
The rail lines to Kyle of Lochalsh & from Glasgow to Fort William are scenic but you can’t open the tinted windows to take photos. So, car is best in these areas.

Returning south, you could go by train down the west side, perhaps stopping off at Penrith to head for Keswick & the Lake District. Chester is another place that is well worth seeing on the west side of Britain. It is also the gateway to north Wales. Alternatively, you could keep the hire car for visiting these areas and that would enable you to detour to see Hadrian's Wall. A hire car would be most useful in Wales as well as the Lake District.

Glastonbury is not worth bothering with but can be done by bus (along with Wells) if staying in Bath.
Buses > www.traveline.info

Train times & fares at www.nationalrail.co.uk
Pue-book longer journeys about 11 weeks out for specific trains to get the cheapest fares. Britrail Passes are not considered good value. Consider a Family Railcard.
https://www.youtube.com/watch?v=fVoWSTHcnmo (A short video of London > Edinburgh by train).
http://www.seat61.com
Also read this post:>https://community.ricksteves.com/travel-forum/england/train-boarding-seat-reservations-missed-connections

I tend to agree about taking a train to Edinburgh and renting a car there. But, if you want to see the Border Country you might want to rent one in Newcastle. This would let you take in Hadrian's Wall, and then visit some of the great Border Abbey's--Jedburgh, Melrose, Kelso.

Or just head to Edinburgh and pick up a car when you are ready to head out into the countryside. You actually can get to St. Andrew's by train--it's just that the last few miles are by bus or taxi. So it can be a day trip out of Edinburgh. Or you can drive and visit some of the interesting sites in Fife--Falkland Palace, the coastal fishing villages for example. Stirling is an easy day trip from Edinburgh by train and Glasgow is less than hour by train from Edinburgh with frequent trains. You could take the train to Glagow at the end of your time and spend a night there, or do a day trip--yes there is left luggage at the Queens Street station per their website. Then, catch the bus to the airport and rent a car there and head out of town a bit. This works well if you are headed north.

Pam