Theoretical: Habitable planet in a binary star system

I hope this is the right Stack exchange for this question. I'm designing a planet as a setting for a tabletop RPG campaign, and basically I'm looking for some help to make sure my idea is at least theoretically sound enough that players won't be completely derailed by my messing things up.

The concept, a very large blue main sequence star, I'm thinking around 100 solar mass, and orbiting that is a red dwarf, somewhere in the .25 to .5 solar mass range, and then the "Planet" is orbiting the red dwarf. My ideal concept is that the blue sun is distinctly brighter, but distance and positioning is such that, to a person on the surface, both suns appear equal in size.

So, the core question here is, is this at least theoretically sound, and which sun would provide more warmth to the planet?

Additional sub-question, what's the correct term for the habitable body orbiting the red dwarf? Is it a Planet, as it orbits a star even though that star orbits another star, or is it technically a Moon?

• I'm not sure if the (percived) size of both Suns can be maintained. If the Planet travels around the dwarf it will get closer to the blue one and so would get bigger and smaller depending on the (sub-) year. This assumes that orbits are roughly in the same plane. If the Orbit of the planet is 90° to the orbit of the dwarf it could work. But I don't know how likely this is, or if I described it correctly. – lokimidgard Jul 4 '16 at 17:01