It can be a fun thing to play around with.

But, if you really want something you can count on (both growing true and germination), I would either purchase seeds or ask around for what you are interested in.

The question of germination from store bought dried peppers comes down to what temperature they were dried at. If too hot, the seeds won't be viable. You also have to consider they may be hybrids that won't grow true from seeds. But, it seems like most people that try to germinate enough seeds from commercially dried peppers will find at least a couple that sprout.

I tried a similar experiment that didn't get off the ground. I took dried chile de arbol from the same type of package and tried the float test in a cup of water. All the seeds floated to the top. This test isn't always accurate but it was enough for me to decide not to go ahead with it. I'm pretty sure they dry these at such a high temp that the seeds bake inside (to save time and money).
If you dry your own peps in a dehydrator, you can set the temp low and use the seeds for planting.

Yeah, it depends on how they were dried. I've successfully germinated seed from some bags of dried pods at WM.

I am growing an Orange Bell Pepper from seed I got out of a pepper I bought in the supermarket last winter.

As long as the peppers are ripe, the seeds inside will likely be viable. For any pepper, just start with a ripe pepper, open it up and carefully pull the seeds out and put them on a flat plate and spread them out. Just the seeds and leave the white pulp behind or you can pull the pulp and seeds out together and separate them after they dry...but they will dry better with pulp removed. After letting them dry for a few days (I usually go 4-5 days), just put them in an envelope and store them in a cool, dry and dark place until you wish to plant them...or plant them as soon as they are dry.
Bruce