Idling engine and braking issue

[mli]

Hi, I own a 2007 petrol 1.4 Polo.

From what I understand when the engine is cold, the engine rpm will be slightly higher when you first start the car. The engine rpm that I've noted down is roughly about 1,200 rpm then it drops to 7/800 rpm a few minutes later. A few questions...

1.) How long does your engine idle for when the engine is cold? The longest I've timed it is about 6 minutes and that's when I've started the car for the second time in the day and temperature was about 7/8 degrees. Does 6 minutes sound a bit too long?

2.) When I'm in a rush I start the car and wait about 15/20seconds before driving off and the engine rpm is still around 1,200 rpm. The problem i'm having is that when I brake, the car is fighting and still accelerates forward and I have to press the brake pedal further more to come to a complete stop, almost like a mini emergency stop. Is this normal? My previous car, a corsa never did this and I also drive an 06 Golf and it doesn't have this problem either. Can anyone shed some light?

Also the throttle body has been cleaned. Thanks in advance