I have discussed this before, in a thread which discussed drinking.
There is no explicit sin in drinking alcohol. Alcohol plays a part in Jewish rituals, and it is drunk every Sabbath for Kiddush. During the Holiday of Purim there is a mitzvah to drink. But the Torah is clear that drunkeness is not something which a Jew should be. Several stories in the Torah discuss this, most notably the story of Noach who planted a vineyard as soon as the flood ended and he got drunk. He was so drunk he was abused by his wicked son, and thus he cursed Ham. Another notable point Torah makes is that a person who makes the sacred commitment known as Nazir is prohibited from touching grapes or grape juice or wine, or any alcoholic product. Also the story of Aarons sons Nadab and Abihu who were consumed in the Holy of Holies for bringing a foreign fire into the sacred place while they were intoxicated. There is also a command that a Kohen cannot perform the holy services while intoxicated, and thus we also do not considers davening while intoxicated to be a good thing. This issue was a part of the story of Hanna who prayed to have a son. Her praying was so intense that her lips moved and she was weeping strongly, the priest thought she was intoxicated.
So the answer to your question, according to my understanding, is that Judaism doesnt consider drinking to be a sin... But getting drunk and wasting time is a violation of many Torah commands. Drunkenness leads to other sins and thus must be avoided. A person who has a yetzer hara {evil inclination} for alcohol should place a fence around it and avoid it. But for most people who have no such yetzer hara, there is really nothing wrong with a little wine with dinner or for Kiddush...