Is kosher food considered halal for Muslims?

Answer 1

It really comes down to the specific food item. Some foods are considered fine within both groups, where others are not. Specific rules about the processing of meats can vary between the two, so it is best to find out about the specific steps used in the butchering of the piece you are interested in to make sure it fits your needs.

Answer 2

It depends on the particular issue you are raising. However, most Muslims feel that kosher food is much closer to halal and can be acceptable as compared to non-kosher and non-halal certified products. In general, Jewish dietary restrictions are more rigorous than Islamic ones, so this is why kosher is usually acceptable. There are two restrictions and issues, though.

Concerning Alcohol

Kahrut permits alcohol while Islamic Dietary Laws forbid it. As a result, items cooked or prepared with alcohol, such as coq au vin or tiramisu, may be completely kosher, but are haram because they include alcohol.

Concerning Meat (land animals and birds)
There are some debates among Muslims as to whether Jewish blessings during the slaughter of an animal is sufficient to qualify as tasmiyah (blessing God in an Islamic context during slaughter). The majority opinion is that since Jews bless the same God as the Muslims for the same purpose, the Jewish blessings count as tasmiyah. There is a minority opinion that the failure by Jewish butchers to say specifically "Bismillah ar-Rahman ar-Rahim" when slaughtering an animal and/or to not bless every single animal, as opposed to entire queues of animals, is sufficient to bar the consumption of kosher meat. This arises primarily as an issue in the Hanafi school of Sunni Islam. No other school has an issue here. There is no other issue for a Muslim eating kosher meat.