of the three i would probably take northshore.
don't know much about weiss, but the people i know who went there were not huge fans of the program. they did, however, love the intern class and are all still friends. i think their biggest complaint was that it was disorganized.
northshore is paradise - nice hospital, good schedule, good teaching, good cafeteria, etc. if i were to go there i would live in either lakeview or lincoln park and then take the purple line or drive to work every day, it's actually pretty fast other than friday traffic.
i'm told st francis is good but i've never been. of the two in evanston i would still take northshore. macneal used to be everybody's favorite, but for reasons i don't understand everyone on this forum now doesn't like it.
based on people i've known in the programs, i'd say resurrection is the cushiest in chicago if that's what you're looking for, and northshore is tougher but still very pleasant and a good educational experience. and that's really what you're after, right?