but separate audio as well, which is not easy at all with a PC.
I agree this is nearly impossible in XP, but it shouldn't be too hard in Vista . . .
Jesse - I'll probably be using Vista unless I get a real hair up my ass to combine my first build project with my first Linux install (not likely). My main concern is making sure I won't be limited by this hardware down the road. It sounds like worst case I'll need an extra video or audio card to make any combination of displays workable.
I retract my "not too hard in Vista" statement. Now getting two separate audio outputs is doable, as is getting two separate video outputs, but how do you get two separate simultaneous user inputs? That is the problem with Vista, it is still a single user OS. To do what you want to do (2 separate home theaters run from the same PC) you really need a multi-user OS. I think you need to do a major rethink on this project. Going with a media-extender for one of the rooms is probably the most bang for the buck. The question is whether it provides enough functionality. You may find that a basic server coupled with a media extender for each room is even more cost effective.
One other thing I'll say on this subject is that I think that Blu-Ray via HTPC is not currently a better solution than a standalone Blu-Ray player and I'm not sure it will ever be. The DRM issues limit the functionality of software players and add just too much complication for DIY. Maybe a couple of years time will fix this, but meanwhile standalone feature sets will increase and price decrease. My feeling is that HTPC is for Internet content, either downloaded or streamed, and standalone players are for physical media.
On that note, would a amplified audio card be worth looking at if I can get rid of my external audio amp?
The only thing like this I'm aware of is the AMD Maui platform and the related MSI Motherboard. There is a fairly involved thread on this product on these forums. Read it and see if you can live with its limitations. The short answer is that, if 5.1 output is sufficient and the HTPC would be the only source; then yes. I am not a fan of this because, thanks to DRM, the HTPC is a long way away from being a viable replacement for cable/satellite STB and standalone Blu-Ray players and, also thanks to DRM, it can't even act as a switching receiver for such boxes!