You should upgrade yourself to get a high-def receiver from Rogers or whoever does your TV (must be either Rogers, Cogeco or Shaw if you're in Ont.), then purchase extra high-definition channels. That TV will be able to hook in to that box with HDMI.
Hope this simplifies stuff for you.
I would recommend Star Choice satellite for the best picture quality.
EDIT:
Star Choice changed their name to Shaw Direct.
Hope this simplifies stuff for you.
EDIT:
Star Choice changed their name to Shaw Direct.