Just search for threads on here for the same questions you have that hundreds of other Indian expats asked and people here answered.
If you're an Indian dude working in IT in Poland you'll be fine. It'll cost you more to get around not knowing Polish but English is common in the cities. But since you'll be making more than the average Pole you'll still be able to save money.
As far as some of your questions:
1.) Are people really as racist and against immigrants as much as what they seem online?
Yes, but mainly against muslims due to events in w Europe. Indians generally have a good reputation and are treated well. Just avoid drunk soccer hool looking types late at night. It's not that Poles are all racists, it's just that we prefer our own kind just like most people and don't want a bunch of migrants to come in and demand we adapt our culture, way of life, and then feed, house, etc. them and their soccer team of kids. Then we end up having terror attacks and thousands upon thousands of rapes just like our next door neighbor. **** that...
4.) How are minorities treated in general in local government offices and such?
Depends on who you get. In general, 'outsiders' even Poles and other Europeans don't get the best treatment at government facilities. Especially if the person helping you is some old lady who grew up through PRL years.
5.) There seems to be some political instability within EU and also with Poland's neighbours. What's the general outlook ?
I wouldn't worry about it too much. EU doesn't want Poland to leave and Poland doesn't want to leave EU.