Do you believe it's true that all animals were created as vegetarians

I did at one time, but now I'm not sure why. The Bible does say some ridiculous stuff, but it never says that. The closest thing to it is in a prophecy about paradise. It says one time that it will happen that the lion will eat straw, in the context of repeating the statement that snakes eat dirt, not that it happened in the past. If you know anything about lions and snakes, while believing that they were designed, you would likely conclude they were designed to be apex predators.

No.

But I have never attempted to read the Bible as a science text.

No. According to Genesis all the animals were created before man and while he provided all the vegetation for them he also gave all of them to man as food.
I do have 1 question about mans creation. While there are various sources I have read 1 that said after all else was created "Now let us create man in our image"
Who is us and our?

Well the Bible indicates that in eternity the animals will be vegetarians.. So it can be theroized that in the garden of Eden when things where still good that all the animals where vegetarians.. But the account does not make any statement on this issue so no one can give an accurate answer on this question..

Yes, before the fall animals did not prey on other animals.

No. Not in the slightest. Not even when I was a Christian did I believe anything that nonsensical.