Stefan,
The family is found on the address in the US census 1930 (ED 61, p 18B), but the street name is most likely MOrton Ave, not Marton.
John A Johnson 31, carpenter, immigration 1922. Wife Ragna M 38, born in Pennsylvania by Swedish parents. Son Marvin K 4 y 3 mo (2 mo?). House is owned and valued to 3600 dollars.
The only thing conflicting with your records would be the sons age, this census suggest he is born sometime early 1926. What source is your birthdate from?
If we guess Marvin stayed on in the house there might be a shortcut for you. If you
go to Intelius and enter the address 906 Morton, Des Moines, IA in the address search, two records are returned. Since the ages of the couple living at the address are given as approx 70 and 79 it is my guess it's Marvin and wife. You can buy these two records for $7,95, and you then get the names plus phone number. You can't get it from the phone book, it's probably unlisted.
You can also try writing the address and hope you get contact. I think those owning the house today are likely to know something about earlier owners, should it be the wrong people. Todays zipcode is
906 MORTON AVE
DES MOINES, IA 50316-1535
Here's a
map for the address.
Good luck,
Jan