I can really only vouch for the 1235 S Clark option since i know people who have left their car parked there for extended periods of time. If you land at 7 the 9 pull out shouldn't be too big of an issue for you. If you checked a bag by the time you collect it and take the metro you shouldn't have too much time to wait. If you are left with an hour or so there are plenty of places to eat/kill time on crysal drive.

Basically here is your plan, park at 1235 S Clark St. take the elevator to the main level. If the weather is bad you can stay entirely underground to walk to the metro. Just look for signs it is about a 7 minute walk. If it is nice out you can walk outside, if you choose this option just ask someone for directions. Take the metro one stop towards hunington (yellow) or fracoashia-springfield (blue). it doesn't matter which one you take. I don't know how familiar you are with the metro, but just for some background fares are distance based so you need one metro card per person. It is $1.35 each way or $1.65 during rush hour.