MAMEWorld Forums - Hardware - Need some advice on computer parts

I'm looking to build a new computer and could use advice about some of the components. Here are the specs for my current build (built Aug 2006):

AMD Athlon 64 X2 4600+
ASUS M2N-E
Patriot DRR2-800 2GB (2x1GB)
HIS X1900XT
Plextor PX-760A (PATA connection)
1 300GB PATA drive (storage)
2 300GB SATA drives (1 boot/storage, 1 storage)
1 500GB SATA drive (storage)
Peripherals (speakers, keyboard, mouse, monitor)

The old computer will be going to my parents to replace their current one and these are the parts I'm keeping:

Peripherals (speakers, keyboard, mouse, monitor)
1 300GB SATA drive (storage)
1 500GB SATA drive (storage)

Everything else I need to purchase, including drives to replace the two that are remaining with the old computer. The primary use of my computer is gaming/emulation, along with other mundane stuff (listening to music, photo editing, watch movies & shows). I would also like to run Virtual Machines for software/OS alternatives testing and to run older OSes for non-compatible software. I have a hard limit of $1,450 to spend on this build, it was $1,600 but I need at least $150 to upgrade the memory and OS on the old computer. Here are the parts I'm currently looking at:

http://pcpartpicker.com/p/nzmO

Normally I would go with AMD, but given their lackluster performance of late, I'm leaning towards the i7-3770. I don't plan on overclocking so, other than the 100 MHz stock speed difference, would there be any noticeable differences during normal use between the K and non K version? Given what I expect to do with this build, would it be possible for me to go with the i5-3570?

How much memory should I be looking at, 16GB or 32GB? Normally I would gear it around what I planned to do, but I've never run VMs before and am a bit confused by their memory requirements.

And finally, we're using Windows XP x86, so both computers are in need of a current OS. It'll be Windows 7 x64, but should I go with Home Premium or Professional? Can Home Premium run VM programs like VirtualBox or VMWare Player without choking?

And a semi related question, are Blu-ray burners worth the $100 or is the technology still too new to be viable? I ask because of the 25GB disc size and the fact that the price per disc has become somewhat reasonable.