Novice,
Sorry I or anyone else hasn't answered. It is such a simple question but so hard to answer. In a cool dark dry spot in the house, most seeds will last a few years. Some are only good for a brief period and some last for years.I'm really not sure about refrigerated. I'm sure it slows down the process, but you must take car to make sure they are complete dry and then air tight. Moisture is not good. Frozen, they can last indefinitely.
Remy

Absolutely most seeds will last much longer when stored in the refrigerator, with the humidity as low as possible. I keep all my seeds in one of the refrigerator drawers with the humidity setting on the lowest position. They are generally in paper packets (some are plastic too), organized in open Ziploc baggies labeled "Perennials", "Annuals", "Herbs", "Grasses", etc. I throw the extra dessicants that come with vitamins, packaging, etc. into the drawer and in each ziploc baggie.

I have had excellent germination on seeds that are 10 years old and older. This Spring, my parsley, basil, and tomatoes are from seeds that were packed for 1997 & 1998 and they have sprouted abundantly.

William Cullina says this in his native Wildflower book: "The other way to slow down the aging process of seed is to refrigerate it. Metabolism involves chemical reactions that are greatly slowed as the temperature is lowered to near freezing, and air-dried seed stored in paper envelops in the refrigerator will stay viable 5 to 10 times longer than seed kept at room temperature."

Here is a general guideline for viability.

Here is a link that might be useful: Seed Viability Chart