How many launches have they done so far, and what were the results?
Seriously? Well not counting their ICBM program.
S-1C Program (Saturn V Rocket First Stage): 12 successful launches, 0 failures.
IUS Program (Booster for interplanetary probes from Space Shuttle): 24 launches, 3 failures (2 Boeing's fault, 1 the space shuttle exploded).
Delta II: 153 Launches, 2 Failures.
Delta III: 3 Launches, 2 Failures.
Delta IV: 33 Launches, 1 Failure.
I mean, do we have any evidence that Boeing has a serious Mars program?
No. The new ULA Vulkan launch system doesn't have it's first test flight scheduled until 2019.
What about re-usable?
Boeing (or really ULA) is developing the Vulkan Rocket. Which is partially recoverable, not fully. [1] The first launch of this vehicle is 2019. The entry level offering is quoted at ~$100mil per rocket (vs ~$164mil for a Delta IV) [2]. While a Falcon9 is $62mil [3].
I see why ULA lost their contract, Musk cut their knee caps off.
[1] https://spaceflightnow.com/wp-content/uploads/2015/04/recove...
[2] https://spaceflightnow.com/2015/04/13/ula-unveils-its-future...
[3] https://en.wikipedia.org/wiki/Falcon_9