I have been getting a lot of packet drops and errors using a wireless security with this router. I also have Mac address filtering turned on. If I was to turn the wireless protection off and leave the Mac address turned on, could anyone potentially hack into my router?
Actually, there is 1 purpose in enabling Extra Wireless Protection (If we are talking about the same configuration. You can find this under Advanced -> Advanced Wireless).
Definition: Extra protection for neighboring 11b wireless networks. Turn this option off to reduce the adverse effect of legacy wireless networks on 802.11ng performance (If you want any explanation of any setting, click on the Help link on the right hand side).
Even with MAC address filtering enabled, you can still be hacked, like thehailo mentioned above. All they need to do is force their NIC in promiscuous mode, and use a program like WireShark to 'sniff' your MAC address, and clone it on their computer. Once they do that, they have circumvented MAC Address filtering.
BTW, WPA is easy to crack. From what I have read WPA2 is easy also using Back|Track 5. I'm not going to put links up to reference it, but can easily be found searching.
If you want to be 100% safe? Run wired. Plain and simple. There is a price to pay with the convenience.