Another tip for your first batch, and another reason to leave the beer on the yeast a bit longer in the primary is to be sure the yeast is completely done fermenting. Be sure to check your gravity with your hydrometer after you calibrate it in pure water.
My first couple batches, I followed the '2 weeks in primary' plan and had a few beers not finish out and a few off flavors (acetaldahyde) that the yeast would normally clean up.
I'm a bit confused. You said that I should keep the beer in the primary fermenter for a couple of weeks, but then you say that when followed this rule your beers had some "off" flavors.
Was this perhaps a typo, or maybe you are trying to say that I should keep it in the primary fermenter for MORE than two weeks?
The recipe kit I have says to do primary fermentation for 5-7 days. Is it ok to disregard these instructions? I'm such a newb....