Yep, that motherboard will work just fine.

That all depends upon which coin you'll be mining; the difficulty level and the availability of pools for that coin. You can choose to solo mine any coin, but the higher the difficulty, the more luck required to find a block. I've heard that solo mining is not very feasible if you have less than 1% of the entire network hashrate. However, some coins may not even have any pools setup, so you'll be required to solo mine. Once you decide which coin you'd like to try, look through the Alt-coin sub-forum to see if anyone has setup a pool for it: https://bitcointalk.org/index.php?board=67.0