I've heard that since my MOTHERBOARD has two internet plugs on it, I could plug two wires in and dedicate them to in/out seperately, largely increasing my connection speed. Is this true?

If yes, how do I do this? Simply plug them in the motherboard and in the router?

My motherboard is an ASUS P5N32-E-SLI.

[file cleanup - saving space - attachment deleted by admin]Your internet connection is most likely a lot slower than the max speed of even one Ethernet card. (Unless you happen to have a 100+ mbps internet connection.)
If this is the case your speed limitation is not your Ethernet port, but your internet connection. The only way to increase that speed is to order a FASTER connection from your ISP.Routing. Operating system that supports routing (LINUX, UNIX, Windows Server operating systems).

The increase is not dramatical, Deerpark advised you well. For small companies/home CONNECTIONS to have more than one connection is a brag - unless you have an 24/24 available Internet server in your LAN and you need redundant connections to internet.