I used to run - a lot. Anything up to 100 miles in a race, and always over the hills and mountains. My preferred distance was 50/60 miles and I regularly won races at those distances. Trained anything up to 100 miles per week. Think I've done a bit of running in the past! Only stopped when the discs in my back got knackered with the pounding, but still hold some records from 30 years ago.
I'm interested in this protection for your instep. Never heard of that before. Sounds to me like you are pronating. That means that your ankle is falling over on itself onto the inside. Happens a lot. Happened to me. Sod all you can do about it except live with it. Yes you can get all sorts of instep and ankle supports. All these do is try and twist your foot into a more upright position. Trouble is that you were born that way, and putting wedges or inserts in your shoe just causes an imbalance elsewhere - usually your knee. Maybe if it had been spotted at birth it could have been corrected, but now your body is set, and there's nowt anyone can do about it.
I used to wear out a pair of racing shoes every year by pronating. Eventually you'll find that the heel cup just falls over to the inside and you are running more and more on that rather than the sole of your shoe. That's life, sorry. How badly you do it will determine if you can run seriously or not. If you've got it bad then you won't enjoy running more than a mile or two anyway. As I said I had it, and so did most of the guys I raced against. We just lived with it.
As for wet socks causing blisters? Unless they are pure nylon that is probably not the case. We frequently wet our shoes and socks before we set off, and anyway we were bound to get wet over the distances and weather conditions we went through. Yes, you might get blisters on pressure points on new shoes, especially as your feet are bound to be very soft at present. Your feet will harden up in time, but you may just have to put up with some blisters as part of the learning curve. You'll probably get some trouble from shin splints and maybe even Achilles/hamstring strains as your body adjusts to the new strains you are putting on it. We never took any special precautions for our feet before setting off on any run - but it takes time to get feet to that level of hardness.
If you really want to improve then you must get out of the jogging mentality. Work out some set routes to run over, with known distances. Keep a diary of how where you went and how you felt. Most importantly get a decent stopwatch and time yourself over each run. Write the time down to see how you're progressing. Work out a routine round your domestic arrangements and try and stick to it. Try not to run in the morning: your body is still half asleep, so always try and train afternoon or evening when you've loosened up. That will cause fewer injuries.
Leave the MP3 player and mobile phone at home and don't have anything stuck in your ears. Concentrate on what you are doing, not what your Twitbook contacts are saying.
Get yourself to a good, I mean GOOD sports shoe retailer. Forget JD Sports - forever. Find a shop where the owner goes out running regularly and get their advice. I hate clubs of any sort, but a running club will give you training partners, and guys to talk over your problems.
Lastly, and most importantly it all depends on your attitude. Do you want to do it, or would you just like to do it. If you want to do it then make your mind up to stick with it. If it's just something you think might be a good idea and you'll see how it goes....then don't waste your time and money.