Wa `alaykum As-Salamu wa Rahmatullahi wa Barakatuh.
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
In this fatwa:
1- It is not allowed for a Muslim marrying a Christian woman to prevent her from practicing anything that is allowed in her faith, say her prayers, fast her way, and do other rituals.
2- As for eating pork, he is allowed to prevent her from it since it is forbidden according to her faith.
For more details, we would like to quote the following:
A Muslim husband should set an example for his wife in morality, tolerance, kindness, loyalty, etc. By doing so, he will call her to the light of Islam without infringing upon her rights.
The Qur’an is not the only Book that prohibits eating pork; the Bible even prohibits it and declares it to be unclean.
In the book of Leviticus, chapter 11, v. 7, we read: “And the swine, he is unclean to you. Of the flesh shall ye not eat, and their carcasses shall ye not touch; they are unclean to you.“
This command is repeated in Deuteronomy 14:7-8: “The pig is also unclean; although it has a split hoof, it does not chew the cud. You are not to eat their meat or touch their carcasses.”
Then, in Isaiah 65:2-4, and 66:17, God issues a stern warning against those who eat pork.
Some people are aware of this prohibition from God, but they say that they can eat pork because St. Paul said, in his letter to the Romans, that all food is clean 14:20. St. Paul said this because he believed (as he wrote in his letter to the Ephesians 2:14-15) that Jesus had abolished the Law with all its commandments and regulations.
He seems, however, to have misunderstood what he heard about Jesus. In the Gospel, according to Matthew 5:17-20, Jesus is reported to have said quite the contrary, as follows: “Do not think that I have come to abolish the Law . . . . ” Jesus then went on in that passage (in verse 19) to denounce anyone who would break the smallest commandment and teach others likewise. He also praised his true followers who would practice and teach even the smallest commandment. One of the commandments, as we have seen, is to stay away from pork.
This is why the true followers of Jesus, holding on to his teachings, did not let unclean food such as pork enter their mouths, so that Peter, the chief disciple, can say, “I have never eaten anything impure or unclean. ” (Acts of the Apostles, ch. 10, v. 14)
With regard to drinking wine, we read in Isaiah 5:22: “Woe unto them that are mighty to drink wine, and men of strength to mingle strong drink.”
And in Leviticus, 10: 8-10, we read: “You and your sons are not to drink wine or other fermented drink whenever you go into the Tent of Meeting, or you will die. This is a lasting ordinance for the generations to come.”
Quoted, with slight modifications, from: http://www.islaminfo.com
Concerning drinking wine, Sheikh Hamid Al-`Ali, Instructor of Islamic Heritage at the Faculty of Education, Kuwait and Imam of Dahiat As-Sabahiyya Mosque, states,
Scholars say that he does not prevent her from drinking that which does not result in intoxication because she believes it is permissible for her in her religion. But he can prevent her from drinking wine that intoxicates as it is prohibited in all religions.
As for eating pork, it is even prohibited in all religions, and as such the husband can prevent her from eating it.
Allah Almighty knows best.