Try to get the discs on the wheels , swapping the discs over every time you swap wheels would be a pain
The sprocket carrier and cush drive rubbers are quicker to swap from one wheel to another but once again it would be better to have them on both wheels , less chance of getting dirt in the cush drive and less hassle , also you may want a differnt size sprocket on the rear for running wets
Changing over wheels is relatively easy and can be done by one person although it is easier with two , practice at home first though ,you don't want to be doing it for the first time at the track
An important thing to remember when changing the front wheel is remove the brake callipers first , after you have undone the bolts , rock the callipers from side to side on the discs to push the pads / pistons back into the body of the calliper before you slide it off the disc , this makes it a lot easier to get back on afterwards.
A good plan would be to go to your local tyre shop and watch very closely how the fitter there does the job , learn from him