Getting the best of my network

I have recently moved into a apartment complex and have a terrible ISP service right now. I am going to be switching to the highest package from At&t but i know there are things to help improve my network. I have a Asus crosshair mobo with "dual gigabit Lan controllers that supports Nivida daulnet technology with built in dual gigabit MAC with extreme Marvell PHY" It supports Teaming and fail over functions & TCP/IP acceleration...
OK with being said i have no clue what any of it means. I have since moved in and get terrible lag spikes in games and higher pings which are killing my experience. I am to the point i want to pull my hair out..so here i am, I'm looking to buy a highend 3party modem and anything else that might give me optimal performance. I dont know if it will help though i hear of people using cheaper stuff and getting the same out of it which confuses me as to how it helps then. i also know i am not using my motherboard features correctly and can't understand how to manage them to get optimal performance (teamming and the dual gigbit stuff, packet prioritzing..)
I' just wondering if some can point me in the right direction to get the most of my setup. Now the more i'm reading the more it seems i get confused about all this networking stuff IE: 10/100/100, and dual gigbit controllers ????* so should i get a expensive modem? and what can i do to my rig now to get the most of it? do i need a network card?? Please any suggestions would be doing me a huge favor. and hardware advice also (changing setting for my ethernet stuff ect..