Two things:
-You can prevent the car from having problems by just starting it and running the car in park for 30 seconds once a week. Since you say you are driving once a week or so, then don't worry.
-The best thing to do if you plan on not driving for a month or more is to dissconnect the negative battery cable and tuck it away such that it can't accidentally touch the batt. post. Buy a can of fuel stabilizer ($7 at autozone) and put it in your tank. This should fix the car right up, and all you'll have to do is hook the batt. back up and check tire pressure.
I would actually recommend the first method though...much easier on the car.
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1990 Trek 330
2006 Trek 7.2FX
2006 Trek 7.3FX (Wifey's Steed)