home PC with AMD 635 built - need your opinion

Computer Forum New Build / Upgrade Advice
1

I wanted to ask your opinion about a home PC I’m building.
needs:

  • Office heavy usage (many Office applications simultaneously).
  • HD video broadcasting (simultaneously with office usage)

build:

  • AMD ATHLON II X4 635 BOX
  • GIGABYTE GA-MA785GMT-UD2H
  • CORSAIR 2GB 1333MHZ
  • SAMSUNG 1TB SPINPOINT F3 32MB
  • ENERMAX LAGUNA HTPC +300

Some questions of mine:

1.Is <AMD 635 (with GIGABYTE 785)>
better than <intel i3 (with, GIGABYTE H55M)> ?

  1. CPU Cooler - is it necessary? Can I do without it?

  2. Computer Case - I want something nice and quiet (better small).
    I got strong recommendation on Antec NSK-2480, saying it is much better than Enermax Laguna.
    Is it worth the size and price? what about NSK-1480 - is it good?

I will be happy to get any other remarks.

Thanks

            Kobi