Originally Posted by
RichardInSF
You can do any hotel you want with that length of time. Near the city air terminal (which has bus service to/from the airport like every 10 minutes) are two hotels: the Inter-Continental and the Park Hyatt. These both are also close to subway stations that will take you most anywhere in town that you want to go to. I'd go to to Nandaemun market and wander around, but I haven't explored Seoul that much.
Actually more than 2 hotels: there is the Grand Intercontinental (original Intercon and usually more expensive), the Coex Intercontinental, the Oakwood.....but all are considered 5 star and not cheap. However sometimes can get good on-line deals.
In between the three is the convention center, next door is the high end Hyundai dept store, underneath is the Coex 'mall' - food court, movie theaters, lots of restaurants and shops. You are in the Kangnam area, and the street fronting Grand is the busiest in Seoul.