What of those TV Safe Margins?

I've got 16:9 HDV (shot on a Sony HVR camera) that I want to put up on the internet - on youtube and as a xvid torrent (so people can burn it onto dvd and watch on their tvs). When I do a simple Burn DVD on PP 2.0, and then watch the DVD on my TV, it cuts the sides off (corresponding to the outside Safe Margin in PP2.0). But if I watch the same DVD on computer, I see the entire frame (i.e., no safe margins).

I realize that I'll be exporting/compressing with something other than PP's Burn DVD option once I'm done editing, but it would be good to know how much frame will show up on the final product while I'm editing. I want my video to be formatted like an episode of network TV -- so what do I do? I imagine there must be a pretty common approach to this... let me know thanks!