Another gentle nudge towards Headcorn (or Lashenden, to be correct), as for reacreational flying there's a good mix of aircraft, characters and opportunities that could not be found so successfully at other places on Jez's list. If the location works for you, it has to be top of the list.
The only drawback of going the route that Mr Furner suggests is that your initial sum will be gone sooner, at trial flight rates, whilst your appetite is almost certainly going to be far greater than when you started.
I don't think I'd turn down any offers, if you are lucky enough to get any; pilots who offer a spare seat are doing so to try to encourage your interest, give an insight into the experience and save you money (after all, you share the roads with strangers whose training and discipline can be dubious). Asking is somewhat different though.
A well-known young man whose nose was against the fence every minute he wasn't at school had a good few hours in all sorts of aircraft before he started his formal training, purely because his enthusiasm and attitude outweighed his youth and wallet. Guess where, too?