Perhaps you are ignorant of history of Pakistan too, read a bit on the massacres that happened in areas within present day Pakistan which had a sizeable hindu population.
As regards to Muslism in Delhi, well they knew Delhi was within India and if they decided to leave for the newly created Pakistan - the homeland for muslims where does the element of explusion come in !!! You mean to say that after fighting for Pakistan all their lives the mulsims of Delhi would have prefered to live in Delhi 