:      "Ohaiyo, Mrs. Lawrence." he murmured.
:      "Ohaiyo, my husband." she was being formal in a teasing
: way.  "Did you sleep well?"

"Ohayou" is spelled as thus.  You might leave out the 'u',
depending on which romanization scheme you use, but an 'i' doesn't
ocurr.

Accually, it's really a matter of preference, and could be spelled ohayou,
ohayo, ohaiyo, ohaiyou, ohaiyoo, or ohayoo.  Since ohayoo ends with a long
o, I personally think that it works best as ohayoo since that best matches
up with the hiragana.  Of course once again, it's all a matter of preference.

Actually, you can spell it with an 'i' in 'ohayou', but it'd be wrong.
You could always spell 'hello' as 'heyllo', but it doesn't mean that
it's *right*. Romaji is just like writing in English - you can choose
either American English or English English ... But you can't make up
your own English words and expect people to accept them. So you can
have 'ohayo' or 'ohayou' or 'ohayoo' and be right ... but 'ohaiyou' or
'ohaiyoo' or 'ohaiyo' are ALL wrong. There is no 'i' in 'ohayou'...
And 'kawaikunee' has ONE 'i' and TWO 'ee' ... but you can also write
'kawaikunai', the real way of writing the word ... But if you've got
Ranma speaking, it has to be 'kawaikunee'.

Whatever your preferences may be, there ARE wrong ways of writing Japanese
words. :p  You can't just expect any old spelling to be 'right'...

Kun-chan...