Co2: Do a search for diy co2, lots of info and tutorials will pop up. You can also find instructional vids on YouTube. Good thing about bettas is that they are labyrinth fish and breathe directly from the air so you dont have to worry about gassing your fish with too much co2 (so long as its nothing extreme)
Lighting: Lights: 10-15 w 6500k bulbs should work fine. CFL's right? You can get the spiral kind that you can find at just about any hardware store. Just make sure they are 6500k, often marketed as "Daylight"[Example
]. However some people have problems with these since they may be to big to fit in the hood. This is usually only a problem with the higher wattage bulbs though. Bulbs of 15watts & less should be fine. You could also get something like this [Example]
. Little more expensive but of smaller girth.
Crypts are slow growers. They are root feeders so you should have root tabs under the plants for best results. I have recently set up a NPT tank (soil based) and transfered soem crypts from my 28g to the 5g. The crypts are growing so much more faster than they ever did in the 28g (only pea gravel). A little over a month in the dirt tank and they are now about twice as large! so a good source of nutrients for their roots IS important.
Hagen makes a fermentation cO2 system for only $30, all you need is sugar and yeast and it does it :< They sell them at petsmart and petco.
This is essentially the same thing as DIY. You could control how much co2 comes out by the levels of sugar and yeast used. less yeast = less co2, longer lasting.