although i hear that there are a lot of Hooligans in most of the big cities, and that they are pretty racist.
Put it in perspective. Poland IS a white country and it's a fact. Whether you consider it good or not is your private issue. What Poles think about it is their issue too.
There are probably more racially diversified people in Poland now, but just to give you an idea about what you are into - until I left Poland in 1987 I saw 3 (that's three) black people in Poland. One was at the airport, the other two were students in the University I went to.
What you see in Poland now is not necessarily worse than say, Astoria (Greek and Italian parts) or Whitestone in late 80's/early 90's. A black fella was not able to buy a house in Whitestone. The neighbors would rather set the house on fire (and they did). Where I lived in Astoria you would not see a black person, except for a delivery truck driver, certainly not after dusk. Heck, as Pole I needed a recommendation from a Greek guy to be able to rent an apartment there.
Change takes time, and I see that's what was needed in some of the parts of NYC that I knew to be very racially tense and uncompromising.