TB is right, a JAA PPL is, while not completely useless, quite unnecessary and more expensive to say the least. An FTO that tries to make you believe that this is what you needs, will also tell you that you will need to ad a night rating and an RT licence, which, conveniently, they sell.
As you want to do an fATPL after (assuming in JAA land), do an FAA PPL to keep, rather the JAA PPL which you give up a couple of months later.