I'd go with the Omni. The Park Hyatt is quieter, the Omni is in a great location to get to the bars on Rush, great restaurants and my fave dive bar "Pippens".

Any comments on Sutton Place Hotel?

Sutton Place is a great hotel on Rush Street for bar-hopping and dining. It's close to the LuxBar, Gibson's and Hugo's Frog Bar as well as Tavern on Rush and Rosebud. It's a beautiful modern hotel as is the newer Sofitel which is about three blocks away. I would say you couldn't go wring with either.

the Park Hyatt is a great, great hotel. i stay there whenever i'm in chicago. beautiful, spacious rooms - central location on Michigan Ave - helpful service.

two+ years ago U2 was in town performing and after the concert we returned to the hotel to hang out in the bar and the band showed up! apparently they were also staying there. and then the next day, Sting sitting next to us at breakfast!

now i can't promise rock start sightings as clearly this was an unusual circunstance - but i can promise you'll like the hotel...

If you want to 'stumble' back to the hotel after hitting the bars on Rush/Division. I'd suggest Sutton Place hotel. It's literally right across the street from 10+ restaurants/bars! I know because I used to live across the street... it's a happening place!
Two other options that are closeby: Drake, Westin (on Michigan Ave), and Sofitel.
Have a wonderful time!

Hope you're getting your hotel figured out.

Before you arrive, check out St. Patrick's day highlights:

http://metromix.chicagotribune.com/

http://www.chicagoreader.com/

http://www.southsideirishparade.org/

I wouldn't suggest Division Street but that's up to you guys.

The best location for what you're after is The Sutton Place! It is right in the middle of all the action, and the hotel's in-house bar is The Whiskey. Can't go wrong.

just want to be sure it isn't very cheesy, full of obnoxious college kids. would like a little sophistication as well as proximity to nightlife.

No, Sutton place is not the type of hotel college kids would go to. The 'younger' crowd goes to the bars on Division more. The Whisky bar is a bit more upscale/dressy. Right across the street is the steakhouse Gibsons--lots of stars go there when they're in town.