Your best bet is to build a case from scratch. You can use a PC ATX style case that comes in hundreds of styles but you would have to hack it up to make things fit. You would be spending at the most 50 bucks to build the case if you go for the proper materials.

All you would need really is some metal snips, a hammer, a saw, a drill, pop rivet gun or plenty of bolts.

For the function buttons you just need a push button for the power and maybe a LED to indicant power. You can just soldier onto the function board or if you're creative build your own function board.

As for a SSD you could use a IDE/ATA to compactflash adapter and toss in a 4GB or 8GB card and use that as the primary drive for OS X then use the 160GB drive for media.

Your current CPU is plenty for DVD and MP4 media. Even if you upgrade the CPU it won't really make conversions any much faster.

You can buy a cheap-o USB bluetooth dongle and it will work just fine. To add a internal USB hub you can buy a USB expansion card that has a internal USB connector so you can just plug in the hub and use a extra drive molex connector to drive 5 or 12 volts to the hub. Or since you're turning this into a DVR you can sodier directly to the logicboard and go the wireless keyboard and mouse route on the hub you plan to install.

Before putting any money into it make two price lists. A list to mod the QS to the way you seem fit and a list for a hackintosh. This way you can go with what is cheaper and also think about future ideas for the DVR.
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