Union Station is a good place to be to overnight, shop and eat - the Drury Hotel is one option.
Avoid East St. Louis. You can get shot there in broad daylight pretty easily.
Stay away from North St Louis city.
Union station is on Market Street. Four blocks north is too far north.
Panhandlers are a scourge in StLouis city. Ranken is a bit north in the city and that is not a nice area generally but the area you are going to stay in is not bad really. The area of and around Union Station is quite nice. Are you a fan of museums? There are lots of interesting things close by. I live a few blocks from Union Station in an old Victorian neighborhood and may be able to do a little tour guide work if you feel like it....
See the Arch and leave yourself enough time to go through the museum below ground at the base of the Arch, and to also walk around Jefferson Park.
Good food is everywhere downtown and nearby — Kimols, Tony's (Downtown) Dominics on the Hill, Charlie Gittos (Downtown), Ruths Chris in Clayton. “The Hill” is the bella Italian neighborhood for food. The Tower Grove area (South St. Louis) is alive with ethnic restaurants of the new immigrants to America. Tower Grove is a beautiful turn-of-the-century (1900s) Park (more wedding pictures there in the Spring than any other) and grand old homes neighborhood. Clayton and West County are America's suburbs personified.
Avoid any area in North St. Louis and East St. Louis, Illinois. Go south and west and you're fine. Go for Imo’s Pizza and a Michelob.
It’s a bit of a drive, but the Churchill museum in Fulton, Missouri is worth seeing. Churchill certainly deserves a place in the conservative pantheon of heroes.
Don’t get lost like in National Lampoons Vacation.
http://www.youtube.com/watch?v=BRJnEbt89w8&feature=related