Untapped Keg lifespan?

[obbie66]

I am just about to start using my new setup and do my first round of kegging.
My question is this: When I keg my beer and carbonate it, do i need to toss it in the fridge for tapping or can i save a few room temp kegs for future consumption? I plan on brewing 20 gallons at a time and my kegerator only holds 10. I would like to keep a stock of 20 extra gallons besides what is in my kegerator. The consumption in my house is about 2-5 gallons a week roughly and i plan to brew at least 20 gallons a month. with a good rotation do i need to worry about spoiling? how long can i keep a room temp keg for? Sorry if i repeated my self...ive been drinking =]
edit: ok to clarify....this is pure homebrew awesomeness anywhere from 6% and up im talking about....not sammy or miller nastyness. kegged in 5g corny kegs. co2 dual tap kegerator.

 

[Yooper]

Beer ages faster at room temperature, so I wouldn't keep a mild or an IPA hanging around at room temperature for a terribly long time. But for most beer styles, aging a beer improves it or at least doesn't harm it.

 

[misterVT]

I just leave my extra filled kegs uncarbonated until ready to serve in my small kegerator, then I force carb. I think temperature has to a lot to do with carbonation levels so I just wait until I get the keg down to serving temperature first so I don't have to worry about carb levels over different temperatures. I do hit all kegs, refrigerated or carbed or not, with a blast of CO2 to purge the oxygen out.