First of all, if you’re worried about the safety of 18650 lithium-ion cells, then you are likely a good candidate for using them. Yes, I know that sounds contradictory, but the only time they become unsafe is when people are too stupid to know that.
Genuine brand-name lithium-ion batteries (Samsung, Sony, LG, Panasonic, Sanyo) are actually quite safe, even if they are unprotected. They have to go through rigorous torture-tests to make sure they don’t explode or catch fire. Stuff like baking them in an oven for hours, and short-circuiting them for hours. That will ruin the cells, of course, but it shouldn’t cause a fire.
So, since you’re paranoid, that’s good. It means you won’t do anything really stupid. I like unprotected cells, because many lights won’t fit the longer and fatter protected cells. Besides, protection won’t stop an internal short or the battery getting crushed.
Just buy a good name-brand cell. The Samsung ICR18650 30Q is probably the best high-drain cell for the cheapest price, and it’s a very good cell. Buy it in the US from mountain electronics, or illum, or even overseas from a site you trust. They are manufactured flat top, but you can also get them with button tops added if you need it.
As for a charger, I use a Nitecore SC4 4-cell charger, but any charger uses the same CC/CV algorithm, so don’t get hung up on any particular model. Even those cheap little micro-USB chargers are fine. Make sure to use a DMM to check battery voltage before and after charging, just to be sure. And, of course, never charge when you’re not home.