Do Blu Ray players upsample conventional DVD's?

Depends on the player, there's not a hard and fast rule of thumb that say all Bluray player do or don't upscale. A note though, most Bluray player do not play SD-DVD's as well as a dedicated SD-DVD player. So even if a Bluray player did upscale, it is not necersarily going to be as good as a SD-DVD that does or even doesn't upscale. Any Plasma or LCD TV that is HD Ready has a scaler built into it anyway, so feed these TV's SD-DVD and the TV will upscale it for you anyway. If it didn't you'd get a big screen with a small picture with a big black border round all sides!! The question isn't does your DVD (HD or SD) player upscale, but if it does upscale does it upscale better than the scaler in the TV?!