The Zeil is a good place to start. Either the Hauptwache or the Konstablerwache station will do. The main pedestrian mall is between those two.

From the airport catch the S-Bahn commuter train toward downtown FRA. Buy the ticket for the rain at the machine before boarding. They are multilingual. Consider buying a day pass or even a family ticket for 2 of you travelling together.

Although Germans ar eknown for Sauerkraut, it's actually only a local dish as has been mentioned earlier. Go across the Main River (the subway/U-Bahn to Schweizer Platz or ngo to the Roemer and walk acrss the Eiserne Steg, a pedestrian bridge). On The Schweizer Strasse there are 2 good pubs to have "Rippchen mit Kraut", a marinated pork chop with Sauerkraut." My favorite is "Wagner" but the "Gemalte Haus" is also good.

As a native Frankfurter who has lived in the US since 1975, I still love my home town!

Enjoy it!

Nobbi