Chanukah is an 8 day holiday so you would wish people a 'chag channukah sameach' on any of those 8 days.
Chanukah starts on the Hebrew calendar date of 25 Kislev, and lasts for eight days. Here are the coinciding secular dates for the upcoming years:
2011: December 20-28
2012: December 8-16
2013: November 27-December 5
2014: December 16-24
2015: December 6-14
Yes.
You shouldn't. Hanukkah and Christmas are no necessarily on the same day, so it would be inappropriate to wish someone a happy Hanukkah on December 25, if that day isn't during of Hanukkah. A better idea would be to look on a calendar to see when Hanukkah falls, then then wish your Jewish friends a Happy Hanukkah on Hanukkah.
It self-explanatory. It means you're wishing someone a happy day on the holiday of Hanukkah,
Hanukkah is a holiday. Not a language. During Hanukkah you would say "hello" the same as on a regular day. You can also greet people by saying "Happy Hanukkah".
Happy Saint Nicholas Day!
Mino Niimaamaa Giizh'koot (Happy Mother‘s Day)
In Kannada, "many happy returns of the day" is often translated as "ಹುಟ್ಟುಹಬ್ಬದ ಹಲವು ಹೋರಿಕೆಗಳು" (huttuhabbada halavu horikēgaḷu).
Wish you a warm Thanksgiving day.
It self-explanatory. It means you're wishing someone a happy day on the holiday of Hanukkah,
The duration of Another Happy Day is 1.98 hours.
You say "Happy St Patricks Day"!
Another Happy Day was created on 2011-01-23.