don't know if your window problem is a common golf fault but i know it's one of the main issues with 6n polos. Have a look in a few polo forums. There is a solution to it somewhere. with them its all down to gunk building up in the cog that the motor turns thus jamming the window.
I had a sticking problem with my rear drivers side electric window.
Well, I say sticking

It was more a case of it would wind down but not up again. You pressed the button in either direction and could still hear the motor running, so that pretty much ruled out motor failure.
On removing the door card (job and a half!

) in search of a solution, it turned out that the regulator was at fault. The metal plate that holds the window glass to the regulator cable is held on by a flimsy plastic attachment(part of the metal plate) which had snapped, causing the glass to drop down inside the window. The rest of regulator mechanism was working fine though.
Off I went to GSF for a replacement, but they only do them for front electric Windows on the Mk3

. So down the road to the local VW dealer ,and I found out that you need a whole new regulator at just under £50 a throw

.
Not really having the time to rummage round a scrappy, I paid up, fitted it, and I haven't had a problem since. It was actually quite an easy job once you get the door card off

I hope this sheds any light on this for anyone with a similar problem