Is this a pretty decent computer?

The power supply is terrible. Trust me, investing in a good power supply will save you money in the long run. You won't need more than ~300W but to be on the safe side get a 550W power supply, try this one: a href="http://www.newegg.com/Product/Product.aspx?Item=N82E16817139004" rel="nofollow"http://www.newegg.com/Product/Product.as…/a