Both versions are correct, just don't use ''would'' with static verbs like be.

"I would go to church" could be used with future or past tense. In the future tense, the person is saying that they would be willing to go to church at some point in the future. In the past tense, the person is saying that they had habitually gone to church in the past; so they went to church over an extended period of time in the past. Think of it as a phrase you would use if you were describing your past weekly habits to someone. "I used to go to church" is also conveying that the person attended church in the past, but "used to" indicates that they no longer attend. Although both can be used in the past tense, the difference between these phrases is that "I used to go to church" indicates that this person no longer attends, whereas "I would go to church" is speaking specifically of this person's past and gives no indication of whether they still attend.

I appreciate it

"I would go to church," can actually imply two different meanings. One meaning is that this person is open to attending church service, but has yet to attend. However, it can also mean that this person is speaking about a time when they were in church (I.e. think of it in terms of describing a memory). "I used to go to church," typically means this person has stopped going to church. Please let me know if you still have questions. :-)