A wireless access point is designed for just what it sounds like; a wireless access point to the network. It can't provide internet access to the network via your dsl or cable modem like a router can.
A wireless router is designed to allow your wireless & wired computers to access another network (usually always an internet connection) and to provide network access translation (sort of like a firewall) to hide your computers from the other network or internet. Some wireless routers include additional firewall features such as SPI (stateful packet inspection) which checks the packets as they come in to ensure that its not someone tunneling unwanted data through an open port that was designed for something else.
I know I might be going a little too deep with this than you'd like. So basically the choice is based upon what you want to do with it. If you already have a router connected to the network that provides your internet access, or if your modem is also a router, then you could survive with just the wireless access point as you wouldn't be utilizing its routing features.
If however, you only have internet access on one of your pc's, or if you're sharing that connection from that one pc to the others, get the wireless router. You can then connect the modem to the wireless router and provide internet access to the others without a "server pc" being on.
The cost is usually about the same for a wireless router versus an access point, in some cases the access points cost more due to the demand for the routers. If I was you, I'd get the router regardless of your needs just so that you could use it's routing functions later if you chose to do so.
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Firecodex
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