The case isn't the source of the USB ports -- the motherboard is. The motherboard just connects with the case connections. So I'd ask what brand/model motherboard this is, specifically. If you don't know, use CPU-Z to find out. Some cases have built-in hubs, so you'll get more than the standard 2 ports.
No, you don't need an externally powered USB hub. There doesn't seem to be any correlation to quality of powered vs non-powered USB hubs. I have one here that randomly freezes up about once a week if I plug/unplug the flash drives a lot. On the other hand, I have a cheap $4 hub on a laptop that performs without fault.
This is one of the very, very few cases where it helps to read user reviews at the site where you're planning to buy it. Or if shopping local, be sure it has a customer-friendly return policy (no restocking fees).
Antec cases tend to be extremely nice. For example:
http://www.amazon.co.uk/gp/product/B...SIN=B0017Q8IAA
That's priced pretty fairly. Most Antec cases start at about $75 USD for the good ones, in stores like Microcenter or Fry's, or even online from
Newegg. (Disclaimer: This particular cases is $60 from
Amazon USA, so I'm betting there's some costs added on EU import.) The Antecs run almost completely silent, yet very cool. The secret is the large 120-140mm slow-moving fans, combined with all-aluminum construction (which is where the costs come from). It also helps that they often have vents on top, and heat rises. Just don't drink or store liquids nearby -- that wouldn't end well.
I've had great experiences with D-Link hubs:
http://www.amazon.co.uk/gp/product/B...SIN=B0002AFZVM
I've had on for almost 10 years now, and it looks identical to that one, and has 7 USB2 ports. (Maybe it's the same model, all these years later?)
For any USA readers:
http://www.amazon.com/gp/product/B00...SIN=B00008VFAF
I need to trash my cheap hub. Maybe I should pick up another one of these in the near future. I'm almost surprised to see the exact same (visually compared, at least) known-working hub still available. Better grab one while it's still able to be bought!