>I will be playing on a 42" (or possible bigger) lcd tv. i will also be adding rotary controllers at some point. so to my question... whould i use the arcade vid card available
You don't need an arcade vid card... you're using an LCD TV, should just take a standard computer to monitor vga cord.
>should i be using a I-Pac or U-Hid or combonation of both.
The U-Hid is the way to go, and would supersede the need for a n I-pac... if I were to build another cab, I would go U-Hid. I commend you on knowing about the U-Hid... clearly you've done your research!