Craniac, the blue tubes/bulbs will be actinics, they can make things a bit harsh. The kelvin the guy was referring to is whats called the colour temp of the light. lumens is a measure of outut or in simple terms (no offence) brightness. T5's are the type of tube and basically means the tubes are 5 one eigth's on an inch, ie 5/8ths of an inch in diameter. btw T5's are better than most other tube technology! Mid day bulbs?? probably meant daylight I gues, this has a colour temp of around 5600K- don't go to sleep on me yet there will be questions!!! mimics the sun!
So this is what I'd recommend compacts are ok, most I believe use T5's. Colour temps to go for are 2 at 10,000K, 2 at 6000K (or 5600K or daylights) and maybe 2 at 3200K (sometimes called soft white or tungsten), I would not put blues or actinics on a planted discus tank.