From what I can gather from growing up watching Rugrats, it's to like, celebrate and comemorate when there were some people in a temple with only a days worth of oil, but it lasted twelve days ish, or soemthing like that. Anyone else have more knowledge?
Why is it called "hanuka" in english? Anyway, what I kind of remember about what I call "Chanukka" ("Ch" being the velar fricative) is that it contains several rememberance days for the rebuilding of the second temple (?), and that what you said about the oil. Families come together, eat traditional food, sing, exchange presents, and every day for the duration of the celebration (11 days?), another candle is lit.
All in all, Chanukka seems related to christmas in so far as it seems to be grounded in a celebration of light in the darkness, too, and the customs seem similar.