Vinyl tile is an easier and cheaper alternative to ceramic or porcelain, and provides some (though not all) of the same moisture-proofing as those hard tiles. Vinyl will work on a bathroom floor provided you have a solid underlayment of cement board or treated plywood. Cutting around the tiles about the toilet drain and the tub is the biggest challenge, so have some spare tiles on hand in case it takes a few attempts to get it right.
Remove the toilet by disconnecting the water line with your adjustable wrench, flushing it empty of water, loosening the two floor bolts and pulling the toilet straight up. Set it in the other room.
Draw two intersecting lines over the centre of the floor, using a chalk snap line. Lay a square at the middle of the lines as you snap the second one, to make sure they're perpendicular to each other.
Spread tile adhesive on the centre of the floor with a tiling trowel, covering the intersection. You will be able to see the chalk lines through the adhesive. Cover more than 4 square feet.
Lay four tiles at the intersection of the lines. Press them firmly into the adhesive and tightly against each other.
Spread more adhesive and continue laying tiles, building out along the lines and toward the walls in a grid pattern.
Lay all the full tiles that will fit, leaving space around the toilet drain, tub and walls where there will be less than a full tile. Let the tiles set overnight.
Measure and cut the partial tiles for the edges, using a tile cutter for the straight cuts and a utility knife to cut the curves around the toilet drain and the tub. Install the cut tiles with adhesive. Let it set for a day, then reinstall the toilet.
Use caution with the tile cutter and utility knife.