Japan PS2 Initial Config. in US/English?

[fun4u]

FACTS:
1) Purchased several Japan PS2s in Asia.
2) Live in US.
3) PS2s came with several Japanese games.
4) changed the primary language to English (can't read Japanese).
5) PS2 boxes, and back of device show model SCPH-15000.
6) System Configuration shows unit version SCPH-10000.
7) System Configuration shows PlayStation Driver version 1.00.

QUESTIONS/ISSUES:
1) PS2 does not recognize Japanese game. Menu keeps appearing telling me to insert "PlayStation or PlayStation 2" game (even though Japanese game inserted into drive).
2) Utility disc included with PS2 is v1.01. Don't know how to read Japanese. Need to convert utility disc to English (unless Utility Disc is not required/desired (see FACT #7 above).