Muzahaka, that case in your OP does not fit either ATX or MATX power supplies. It's an ITX case, and if you look at Newegg's top down picture of the case, you'll see there's a small PD (power distribution) board at the front of the case. These are commonly called Pico PSUs. Newegg does not sell them.
Looking for a higher wattage PSU for that specific case? Look here.
That site deals specifically in ITX parts. Some of their enclosures are pretty neat too. For what you have in your OP, I'd say the 120w model Pico PSU is good enough.
EDIT: Also, someone else recommended a GPU addition to your build. Sorry to say it, but with that specific ITX case, a GPU cannot be added because it does not have an expansion slot, and the case itself isn't tall enough to accommodate one.Edited by jamesman32 - 8/22/11 at 6:12am