Hi
Just to echo what most people are saying on here - don't pay any money up front despite any incentives the school might offer. I know people who unfortunately have lost thousands of their hard-earned through schools going bust so its just not worth it. Personally I saved up all the money I needed (about 7k in all) and put it in a building society where I draw money out when I need it. In the mean time its earning me some nice interest so it sort of balances out - that and I trust my highstreet building society more than a flying school in terms of financial stability!
Its taken me almost 18 months to get to where I am and I would say there have been times when I needed that extra "refresher" lesson but after that I've been fine. Thats a job issue though and I wouldn't recommend "stretching it out" like I have. So in that respect its probably best to get it all done as soon as you can when its all fresh in your memory and you are in the "zone" as it were.
I'm almost at the end of my PPL now and my advice to you is not to worry about the flying part. I used to have a fear of flying even when going on holiday but I'm now totally comfortable flying and don't even think about my fear anymore! I think once you are in control it takes your mind off it and you soon forget your fear! That and you'll have enough to cope with in the busy cockpit environment anyway!
Good luck!