Toilets, Sinks, Showers, Tubs and Disposals - toilet/flooring question

I pulled up the carpet in my bathroom getting ready to put down some vinyl tile, and I'm not sure what to think. There was tack board (I think that's what it's called) to hold the carpet down all around the toilet except at the very front the tack board was actually partially underneath the toilet. So, I'm guessing that means I'm going to have to take the toilet up at least partially to remove the tack board, and in that case am going to have to replace the wax seal? I guess I should take the toilet up regardless so I can put the tile under the toilet any way. And then I'll probably need to add a flange, is that correct? If I add a flange and the new floor doesn't meet the toilet, what do I need to add to the toilet?

And do you think this means that the floor is not level in front of the toilet? I can't imagine how the seal is keeping the toilet from leaking as it is now.

So many questions, so little time! ;)

I agree that you should remove the toilet to do what you need to do. Vinyl tile should not be thick enough to alter the setting of the toilet or need a another flange. Should you find that the floor is unlevel enough to need a tack strip (probably 1/4" thick?) to level the toilet then you will need some toilet shims. These are readily available at home centers. Check the floors level before doing anything and then you will know what you need. Good luck and reply back with any questions.