When I'm at ORD I usually stay at the Renaissance Suites O'Hare, which has blue line stop next to it. Easy into the city & to ORD. Their exec lounge is open if you get a club floor room or have status. Has restaurant & bar. Might be able to use your Amex & Chase points.

It's been a long time since I've stayed at the Hilton, but it's certainly convenient to ORD & blue line as well.

Cheers.