Questions about Egglaying, Fertlized Eggs, and other things!

The way you can tell the difference between fertile eggs a non is whether it's a blastodisk (germinal disc that has not been fertilized) or whether it's a blastoderm (fertilized, seen with concentric rings) if you have trouble from there then I would just try candling and hatching it out. If you want to breed birds then it is a good investment to go get an incubator. Brinsea's are good incubators.

 

The brown spot in your egg was likely a blood spot or meat spot. Normal and has nothing to do with fertilization. A hen can hatch eggs but you're probably best off getting an incubator so you can hatch eggs on your schedule and not have to wait for a hen to go broody. You can't chose when to have a hen hatch eggs. They're either in the mood or they're not. Most chickens are mostly not (there are always exceptions!)
You can easily find pictures of fertile chicken eggs with a simple google search. That will help you see the difference in what TwistedFeather was talking about.

How much light depends on how old they are. Often, first year pullets will lay right their their first winter. In general, 14 hours or so is probably ideal. There are a lot of opinions on whether to light one's coop. Again, a search of the forums using the little search box near the top of the page will help you out a lot!

Anything else you should know about what? Hatching eggs? You're best off going to the incubating and hatching forum and reading up there. You probably won't even have to post your own thread, there are plenty of articles and threads to read that should keep you busy for hours