You would want to install the whole BB install to your PC's internal drive (likely c:\)
The Everything Pak is 65 GB. So you'd need to have that much space available. Most PC's come with at least 250GB, so that shouldn't be a problem. But some come with Solid State Drives - great drives, but only 80-120GB in total. So I wouldn't get one with a SSD as an "ultimate BiaB PC", unless there was another drive on that PC as well.

Other than that, CPU horsepower is good - faster the better. And fast hard drive is good too. Of course you'd want the latest goodies, like USB 3.0. If its a laptop, the quality of the built-in speakers would be important too - since you would be using that a lot.

You can measure the speed of your PC by a geekbench test (free http://www.primatelabs.com/geekbench/ ). Most new PC's are above 2000, and the real screamers are up around 8,000. I program BB Windows on a MacBook Pro (running Windows 7 under Bootcamp) and its' Geekbench is about 3,500. I also test it on my older XP laptop with a geekbench of 1,100, which works, but obviously things are slower.

Have Fun!
Peter Gannon
PG Music Inc.