I was wondering if I could get away with normal boots, the typical ones the ladies wear in Poland.
the fashion now is for a lower heel. so you should be ok
And in regards to trousers, are jeans ok in the snow?!
most women wear jeans in winter. the extra layer would be tights/pantyhose
the way to keep warm in winter... is to keep moving
keep an eye on the long range weather forecast and buy clothes accordingly.
if the weather is really bad you won't be going out, will you ?