2) Do you think paypal may accept bitcoin in next years (3-7) or it is impossible ?
3) Do you think bitcoin will be better than paypal ? when will happen ?
4) which better for now PP or BTC ?
1) Yes, it may happen sooner or later.
2) Yes, 3-7 years is a quite long period of time, so I'd say it's absolutely possible.
3) Paypal is currently cheaper and faster than Bitcoin. The pros of Bitcoin are that it can be anonymous and you can send any amount you want to anyone. Paypal on the contrary has string limits and regulations.
4) As already said, paypal is better only because it is cheaper and faster. On every other aspects Bitcoin is far better...