I lied, I was a bit curious about Mars's atmosphere (after I instigated fights with the "masters of space travel" to amuse myself) so I looked it up. Mars's atmosphere is 95.32% Carbon Dioxide(CO2); 2.7% Nitrogen (N2); 1.6% Argon (Ar); 0.13% Oxygen (O2); 0.08% Carbon Monoxide (CO). Ozone is O3, so we shit out of luck there. The solar winds blew that away. It did have a magnetic field at one time. Remember the movie, Core? At least that was what I think it's name was. It's kind of like that. I doubt we'll be building a machine to drill into Mars's core anytime soon though.

Read the first link, it's prolly the best info you'll find.
http://science.nasa.gov/headlines/y2001/ast31jan_1.htm
http://en.wikipedia.org/wiki/Mars#Colonization_of_Mars

Check the link below for info on Earth's atmosphere. I think a lot of this was explained in school from grade four for every year up to high school and prolly explained in biology (I was a physics and chemistry guy).
http://en.wikipedia.org/wiki/Earth's_atmosphere

Now this is what I would like to see. USA exporting immigrants that don't know English to Mars to build their colony. I doubt many people are willing to spend 10 years of their life in a tin can. But if you paid an immigrant minimum wage, and travel time, I'm sure they'ld do it. If you remember history well, you'd prolly realize that making a colony far away from home isn't such a great idea.