"Also, how is it to get luggage on the train as well as safe guard it on the trip? I once had to travel on a rush hour commuter train from Gatwick thru London to Hertfordshire with luggage & it was awful - drag luggage up stairs & stood next to it all the way!"
Your other questions have been answered; so I will say, travel light. When you talk about dragging luggage around, hauling it onto the train, it is an indication that you may be taking too much. It is our tendency as travelers to think we need a different outfit of clothing every day. That is not true. Many travelers find it liberating to travel with the bare basics; two pairs of slacks, two tops, extra pairs of socks and underwear, one rain jacket, or a similarly pared-down list. Remember, you will be wearing your outfit number three; that which you wear onto the plane. Many people here on the Helpline travel with one carry-on bag plus either a purse or a small day pack or messenger bag with maps, guidebook, camera, water bottle, etc. in that. Many experienced travelers have ditched the large, overstuffed rolling bag because it is far too much trouble to drag around. Have a look here http://www.ricksteves.com/travel-tips/packing-light at Rick Steves' advice about packing light. And the two people pictured in this photo are probably still taking about twice the amount they need. Remember what Douglas said, "Don't pack too heavy, you will have to get the bag into the train."
You mentioned "want to travel to Durham/Hadrian's Wall & on to Scotland". At Hadrian's Wall, you may have all your luggage with you, and have to carry it around with you. At that point, you may wish you had brought only a backpack with you. Getting off of the train, going to see a sight for the afternoon, and then getting back onto the train to travel to another city sometimes leaves you no option but to carry it with you. Sometimes there's a luggage storage facility at the train station where you can drop your luggage and pick it up later. Always check for that. Have a great trip!