Ah, thanks for the response.
I might not upgrade my OS yet for now, since I am waiting till I get the new mobo. As for the plan of my sister's pc build, as of now here are the specs I am aiming for...
Name of machine: Project Reisen
Mobo - Gigabyte GA-970-D3 (Once I get my hands on the Asrock mobo)
Processor - AMD Phenom II X4 960T Black Edition
RAM - G.Skill DDR3 2 x 2GB 1600MHz Kit
GPU - Palit GTX460 1GB
PSU - Seasonic M12II M620W Modular 80+ Bronze
HDD - Seagate Barracuda 500GB SATA
ODD - LG DVD-/+RW 24x
OS - Windows 7 Home Premium 64-bit
CPU Cooler - Coolermaster Hyper 212+, OR, Coolermaster GeminII M4
Casing - Coolermaster Elite 360
I might reconsider getting the 2 x 4GB ones for RAM, but as for now, it stands. And yes, After some thought, my family doesn't really need the gimmicks of the Professional and Ultimate. So, how do you guys and ladies think of the proposed build? Will the Elite 360 do justice in keeping the system compact? Please do note that Silverstone casings are out of the question as they're really pricey here in Singapore. Myself, I would have gotten the Antec NSK 1480 for one of my mini builds, but it's shelved for the time being (Well, not really, the Antec casing was actually supposed to be part of my dad's HTPC build, until the gaming part came in, aka that GT440).
And down the road, I do plan to surprise my dad by swapping the GT440 for a GTS450, or a GTX460 as a birthday gift. By then he'd wonder why his HTPC could run NFS: The Run at high settings, haha.