Hi,
Congratulations on not choosing carpeting.
1. Flooring always goes under refrigerator and slide out stove. No need to install under dishwasher unless it's out. Good idea to screw the adjusters in and shim it up as much as possible for easy future removal.
2. You can NOT install tile directly on a single layer of plywood subfloor, and I don't recommend installing over plywood no matter how many layers you have. You have to install either a cement backer board or an isolation membrane such as Ditra. What mortar and what laminate are you referring to?
Before you start you should make sure the subfloor system is stiff enough for tiles in the first place. Let us know the size and spacing of the joists and the unsupported span of the joists. Also let us know what type of tile you're considering and which specific setting products and methods you're considering.
Jaz