That was easy! The Babel Fish says the answer to the next code can be found in the Land of the Rising Sun.
(pick up "123 bar" in lower left screen)
Riddle 2 (Babel Fish translator)
There is this many number in alphabet
(pick up "ABC bar" in lower right screen)
the army of darkness was raised the day the earth stood still
(1 word per box)
klaatu barada nikto
Riddle 5 (Caesar cipher)
(if copy/paste doesn't work, re-type all apostrophes)
One day, Charlie and Oscar went out to the Delta to listen to some music, but there was too much of an Echo. Charlie said, 'we should go somewhere else.' Oscar replied, 'let's ASK Dvorak, I hear he has a good DSK system.'
Riddle 6 (Dvorak keyboard)
Halt, Private! Take a step back, and maybe I'll let you pass! Just FYI.
Riddle 7 (NATO Phonetic Alphabet)
(1 letter per box)
Riddle 8 (Arnold/Ottendorf cipher)
(must have spaces)
whose base are all belong to cats
(other spellings acceptable)