I don't know if they are still available, but years ago when I lived in the UK the best off road trainers for most conditions were Walsh fell running shoes. They seemed to grip well on ice/wet rocks etc.
I would suggest you go to a club sooner rather than later. A good endurance coach will be able to give you good advise, and more importantly SEE you run. Just bear in mind that as with all types of fitness the biggest improvements come initially.
EG - I played football until I was about 27 and then ran 30.43 for 5 miles off a few months training. I then took up running more 'serously', but it took me another 10 years to get down to 29.08. BUT we are all different and you have the advantage of being younger.
It sounds like you are really keen, so get to a club and meet like minded people - you will love it!
Try making a commitment to run - either to friends/relatives (by telling them you what you intend to do) or by finding a club or someone to run with (its harder to make excuses to yourself if you are intending to run with someone else).
Also its much easier to run earlier in the day....the longer you wait the harder it gets to put your kit on!
Finally, don't think too much about where you will go, how far it is and what it will feel like......Just do it!