This didnt work on the tv in my hotel. Alternate that worked for me:
hold both menu buttons as above
menu didnt come up, but channel info did
when this appears, press "ok" button on tv
this brings up menu where hotel settings can be altered.
hope this works for anyone that couldnt get other methods to work.
EDIT: have to do the unlock thing first: hold menu for 5 sec then "1105" there is no notification that this has worked but without doing it first, the menu access above does not work.