Germination time is determined by the soil temp you maintain. Most varieties will germinate within 3-4 days with 75 degree soil, longer - 7-10 days with cooler soil.

best way to go about this is to use individual pots.

Individual containers for each variety, yes, but not necessarily "pots". Any shallow container with drain holes and 2-2 1/2" of seed starting mix works fine. If you use deep pots then only put a couple of inches of mix in them.

Once well germinated they are then transplanted into individual containers.

Plastic domes are strictly optional. Newbies like them until the discover the problems they can cause. They are not required for any reason and experienced growers seldom use them. If some sort of dome is used then yes, it needs to vented for air or removed periodically to allow for air circulation.

There is a great FAQ on how to grow tomatoes from seed as well as other FAQs here you might want to browse through. Just click on the blue FAQ button near the top of this page.

Good luck and enjoy your tomatoes.

Dave