New Years Day Words
1) あけましておめでとう akemashite omedetou - lit. dawn (of the New Year)-congratulations
2) 新年おめでとう shin nen omedetou - lit. new-year-congratulations
WRITTEN IN NENGAJOU*
2) 賀正 ga shou - lit. joyful-New Years (正 is an abbreviation for 正月 shou gatsu - which means New Year's day or the month of January)
3) 迎春 gei shun - lit. welcome-spring
4) 謹賀新年 kin ga shin nen - lit. respectfully-joyful-new-year
5) 頌春 shou shun - lit. exalt-spring
*Nearly every Japanese family creates 年賀状 nen ga jou New Year's cards and hand them to the Post Office for delivery early to mid December. The post office sorts them and gets them ready for delivery early New Year's Day morning. It is a major event and the news on New Year's day always has coverage of teenagers on bikes delivering the 年賀状 as a アルバイト (part time job).
NEW YEAR'S CUSTOMS (different from the customs at the airport)
Note: I won't go into great detail since Wikipedia has tons of close-up info on each, but I will organize things so you just have to click to learn more should you wish to!
Osechi boxes [http://en.wikipedia.org/wiki/Osechi ] and Mochi (rice smashed until sticky) [http://en.wikipedia.org/wiki/Mochi ] are eaten:
Yummy, but don't eat it too fast since you can easily choke on it!
And of course New Year's Eve is spent watching 4 hours of 紅白 kou haku - NHK's (National television) where the talent from the past year sing and entertain the night away.
Here are a few relevant pages from www.thejapanesepage.com:
雪男 - Yuki Otoko - Abominable Snowman
雪女 - Yuki Onna - The Snow Woman
寒中水泳 - kan chuu sui ei - Polar bear club
(Yes, every year you also see old men rush into the seemingly arctic waters to prove they are... I am not sure what they are proving.)
雪の言葉 - yuki no kotoba - Snow words
雪だるま - yuki daruma - Snowman
And if you want to have fun, you can pretend the 年賀状 you received from your friend is really a 果たし状 hatashi jou - a letter of challenge (to a fight) and confront him about his very nice 果たし状
One last little bit... Recently with abbreviations and corruption of words found on BBSs, Blogs and chat rooms there have been some interesting new words pop up. One is もちつけ！ mochi tsuke! which is a corruption of 落ち着け！ ochi tsuke! which means "calm down!" This is just perfect for New Year's day - especially while eating もち. Of course if the person you are talking to doesn't eat and breath computers, they won't have the foggiest idea what you are saying!