Fertile eggs are good to eat.. many people will go out of their way to find only fertile eggs to eat. They are not better or worse in any way than non-fertile eggs.
There is a small white spot.. pea size.. small round.. flat.... not where the umbiblical is (the white, cloudy, kinda string on the side of the yolk, is NOT SPERM, it is the umbiblical cord of sorts), the white spot that shows us it's fertile is directly on the yolk and flat.... just a little bullseye. Your fresh eggs look better, taste better, have less "white cloudy"... and may have a tiny blood spot, sometimes, which is harmless and safe to eat.
If you get the book "Raising Chickens for Dummies" it has a picture... and explanations for all of this. Very helpful book.
Hens are mostly bred for egg laying, not "baby making".... so, they mostly lay and egg and leave it... you collect the eggs everyday.. take them in, wash them with cool water, and dry them off.. use a little scratch sponge if there are tough spots or poop on them.. NO SOAP.. dry them.. put them in the refridgerator. (Save your egg cartons from the store.) If you miss an egg one day and find it the next.. it is still fine to wash, refridgerate and eat... in Winter, I will throw away ones that freeze over night, outside, but this is rare.. as they are laid in the coop and don't freeze there.
You are not eating baby chicks (or sperm) if you eat fertile eggs. And, once you start eating fresh eggs.. they taste so much better than the very old eggs you buy at the grocery store.... you will be hooked and never want "ol' store eggs" again.
I think that most of my hens started laying about 5 1/2 months old... or two weeks after the rooster "got her". The roosters start mating (and fertilizing eggs) about the same time, maybe a couple weeks earlier depending on the rooster.
If you want to hatch eggs, you either need a hen who will "go broody" and sit on the eggs, hatch them and raise the babies, OR you need an incubator (not cheap)...
If you want a chicken to hatch eggs for you.. get a broody breed, add a Cochin or Buff Orpington to your flock.. just be careful, anytime you add a chicken, you have to isolate and quaranteen them to be sure they are well and healthy for a few weeks -- three or four weeks before putting them in with your flock.
goldies99 is right.. you can eat fertile eggs forever and never hatch any..... and you won't be eating babies... they are safe and good to eat... we all eat them, and we sell them and sometimes we hatch some, just for fun or profit.
Throw away any eggs that you have kept for days.. or that you don't know how old they are... or that you have tried to warm with a heat lamp. And, just start fresh. Your hen is laying those eggs for you to eat!! They keep in the refridgerator for weeks.
You only need one rooster for that many hens... two will be hard on the hens.... pick one. Avoid any "aggressive" rooster. If a rooster comes after you, people, he has to go. A good rooster protects the flock, lets them know when he finds food, lets them eat first.. lets them know when danger is near, etc.. He sounds the alarm, and which one are the hens following, if any yet? Which one do the girls like? Which one stands up tall in the middle of the yard or flock?
Now.. you will also need to feed laying pellets... get some supplies on hand for if there is an injury or illness in the flock. Read up on Eggbound, Worming, injuries, etc..
Get some Sevin Dust, Blu Kote Spray, Vet Wrap, Neosporin, Betadine.... go to a local feed store and ask them about supplies for a new flock. You might want to get some Valbazen and syringes (no needles), some Duramycin 10 (Tetracycline) powder... some Pedialyte or some Vitamin and Electrolyte powder... some oyster shell for on the side -- a supplement to their food. Some Apple Cider Vinegar to add to their water (1 TBLS per gallon).
And, be sure to use Pine -- only Pine if you use shavings instead of Hay for the nesting boxes. Sand is a good floor for the run.
How old was your "old" hen that died?
Oh, and you wash the ones you are going to eat and DON'T wash the ones you are going to hatch, if you get a broody hen or incubator.
Take care... Best of luck....
Found just what I was looking for.. as I always do here. This is such a wonderful site, I would be lost w/o it! 
