Just do EXACTLY what is said there, then enter the code for DVD driver 1.01 I posted here. There's no other way to unlock the code insertion menu ... After it's unlocked, it's saved to the dongle or memorycard save and you can easily access it by pressing select.
Put dongle (memorycard in port1 if you using dongle, as that PS2 needs to read DVD driver from memcard) or memory card in port 2
(both DVD driver and DVDregionX saves will be on the same memcard)
Turn the PS2 on while holding L1+L2+R1+R2+Select+Start (this is the command to reset the dongle) then press X to open the CD tray. Turn the PS2 off on the rear switch with the tray open.
Turn it on again and reset (this doesn't matter how now. Just get the DVDRegionX to boot)
At the region select screen press select button. It now should show you the code entry screen ... This simple
SCPH-10000_GH-001 SCPH-15000_GH-003 SCPH-18000_GH-008 SCPH-30001_GH-005 SCPH-30000_GH-016(V4) SCPH-30001_GH-010(V4)
2xSCPH-10190, 2xSCPH-10350, 2xSCPH-10280
"**** j0 hackers!"
-Sjeep (As seen on TOXIC OS ELF...)