1x9 cross check help

I've haven't had a bike in a long time (about 10 years!) but after much reading up on here I've decided on a cross check. Its mostly for commuting on road and some dirt tracks on the way to work. I'd like to set set the gearing up 1x9 with something like a 11-32 rear cassette with a short cage (better for chain tension?) xt rear mech. What I'm not to sure about is what chainset to use. I'm thinking say a 42t chainring but I've been told to go with a double with the outter ring as a chain guard for chain drop and the 42t on the middle. I've been looking at the Stronglight Impact doubles with the idea of getting my mate to grind down the outter as a chianguard and putting a 42t on the middle or getting a TA Cyclocross Guard for the outter. Also, for the chainring I'd be using would I be better with a single speed ring like a Salsa to hold the chain on better? Then again, would this be the answer to all my prayers....

http://www.xxcycle.com/php/_all/shop/impact_rohloff.php

Sorry if any of this seems a bit odd but I'm pretty new to all of this and am trying to get my head around it all;-)