Basement walls and floors too? Is the concrete in good shape? Any moisture issues? If this is an industrial application with heavy traffic? Is this a hospital or school environment with strict but ridiculous paint VOC mandates?
Quick answer is I would use an latex acrylic product for the walls. Semi-gloss I suppose but no reason you have to. A bonding primer or even a concrete/masonry sealer might be called for underneath.
I personally like latex acrylic products with epoxy reinforcement as found in something like Benjamin Moore's Porch and Floor paint for concrete floors. You can put urethane reinforced oil based porch and floor paint on concrete floors also but other oil based products may react with the concrete and fail quickly. There are some nice but expensive industrial coatings with silicone and nano-tech for anti-graffiti applications.
If it is concrete block you will want to apply with a heavy nap roller cover at least 1" thick and chase it with something like a 4" brush.