Today there are really only two choices for 'plastic' pipe used inside a home. The oldest one is the yellowish, rigid CPVC. I would personally go with the newer and increasingly more common PEX. There are two sub-types of this kind of pipe. One is the type that you put a reinforcing band on it, use a very expensive tool to expand the end of the pipe, then drop a fitting into the expanded end. The pipe than contracts around the fitting. It works very well and is very durable but as stated the tool is expensive and the operation of it is a bit of a pain. The other variant uses brass or plastic fittings that are held on by a crimped stainless steel band. That tool is not near as expensive and I know that a my local plumbing shop will lend it to you. This type of pipe is also durable and semi-flexible so it allows you to avoid many joints that you would need with rigid plastic or copper.
This pipe also comes in many colors. They are simply intended to identify what they are carrying. The color has no actual bearing on hot vs cold, etc. Copper, IMHO, is out. It has become very expensive and is messy to solder the fittings.