It just occured to me that I neglected to mention that I'm arriving on a Saturday morning--surely it won't take 3 hours to get to 5th arrondisement on a weekend?
At any rate, I'm opting for the Sheraton breakfast. Dump our bags at the front desk, fill-up a bit and then hit town.
As for the wine bar at rue buci with the toast with foie gras--I've read about it in other threads and have already got it down on my to visit list!