Have a read through this excellent Lumicon filter guide. It will tell you what the different nebula and colour filters are best suited for. The good thing about this guide is it details how nebula filters can also be used on the planets:
http://www.lumicon.com/store/pg/15-L...a-Filters.aspx
Polarising filters are pretty much neutral on colouration. They are used to reduce brightness, when used on their own, or allow for variable brightness control by using them in tandem and spining one of the filters in relation to the other.
Colour filters are used to tone down some colours so that different features become more readily visible. Just note when using colour filters on the planets, those features you are looking for won't necessarily stand out like the proverbial doggie's, nor immediately obvious. These features may become brighter or darker too. It is then upto you to be able to interpret what the image shows.
One last thing about colour filters: If you are mad keen on getting them, ONLY select two, three at most!!!! You just will not use them all that much. Nebula filters are a different beast. If your scope is under 6" in diameter, your best options are either a broad band filter or an OIII. The other filters will and do work, but the amount of light that they actually transmit is so small as to make them impractical for smaller apertures.