Hi Pilot!
First of all, have you flown a light aircraft before? If not, I'd suggest you go for a trial lesson before you commit loads of money up-front. I'm sure you'll love it - but every now and then, someone discovers that actually the sensations of flying aren't all that pleasant, and I'd hate to see you lose a large sum of money if that happens to you.
As for finishing in one month - it's unlikely you'd be able to do that in the UK, because the weather is so unpredictable. Many people do acheive this by going to the USA for 4 weeks, but then they need a few hours training when they get back to Britain. And there is a general opinion that these "fast-track" PPL courses don't produce such good pilots - see this
thread on the Instructors forum for a detailed discussion.
However, I wouldn't let that worry you. If you have the time and the money, I'd fly for 5 or 6 hours a week at most. Any more, and you'll become overloaded with information - especially because you'll have pre- and post-flight briefings for most, if not all, flights, as well as having to study for some exams. And once you start college, you can continue to fly 1 or 2 hours each weekend. Many people get their PPL by flying only at weekends, so this really isn't a problem.
Don't worry about any equipment at first - the school will provide everything you need. You will need to buy things as you go - a flight computer for figuring out how the wind will affect you, several books, charts and various other interesting bits and pieces - but your instructor will advise you on this as your flying progresses. You won't need to buy a headset at all, because every school will have headsets to lend you, but many people like to have their own one anyway. See how you feel after 20 or 30 hours.
Good luck, and have fun!
FFF
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