This is quite easy to do, but was hard to find out how. If you want your website to always be centered no matter what monitored is being used. Do the following:
1. Make a new table.
[Rows = 1, Columns = 1, Width = 100%, Cell Padding = 0, Cell Spacing = 0, Border = 0]
2. Check inside the table and set: Horizontal align to "center", Verticle align to "middle"
3. Now make another table of any size inside the one you just made and it will always be centered.