SilverstrikeOpen comb is more aggressive (the blade is more exposed) but gives you a closer shave. Closed comb side (blade is less exposed) is a milder shave that is easy to use IMHO. If you have a heavy beard the open combed side may be of value to you. Although I would recommend starting off with razors such as the Edwin Jagger DE89, or the Merkur 34c which are also cheaper and highly rated/reviewed.
SilverstrikeAlso be sure to find a blade that is suitable for your skin/beard type. It can change the whole experience. If you haven't looked in to lathering with a brush, that may be information you will be interested in too. Good luck!
TheGrouchWhat's your opinion on 'swapping' blades out? I recently bought a Merkur 34c, but realistically I only shave once a week. I was planning on just going through all the extra blades I bought and doing a 'is this better than the last one' test.
deskjockeyI haven't tried every single blade out there yet, but I like the idea of trying different blades. Although, I would recommend giving each blade a few tries before determining the quality of the blade. You may just have off days shaving and get a few nicks here and there. I am using shark super chromes at the moment and have quite a few blades to try myself. If you find you are comfortable with a certain blade I would actually stick with it until you have issues with it. As they say, "If it ain't broke, Don't fix it!". Enjoy the 34c, it's a really nice razor : )