I guess we did kinda end up hijacking your thread before, but it'd be better if you just continued that thread rather than start a new one. I believe Linux_0 posted a guide on getting Blu-ray working with Linux. I have never heard of your gfx card before (perhaps it is a newer one) and I also can't speak for your tuner card, but everything else seems to check out OK. I have a system that is similar to yours and it works fine w/ linux, but I think you will just want to check in on your tuner and your gfx card to see if there are problems. A google search on either of those are likely to get you quick answers.
Also, AMD's graphics support for linux is getting way better than it was before so you may be in luck there.