By looking at the picture for the card reader, it doesn't look like USB interface, even though it says it is. It looks like a 10-pin connection which I couldn't see a clear picture of your motherboard to see if it has one. It probably does though because I know mine has an opened one or two.
A 500Wat power supply would be plenty. The thing is a lot of those power supplies that come with cases are cheaply made. I've had two friends that have both used the power supplies that came with the cases, and both of them died within a month or two.
If your only using low end 2600 cards, then you could probably go with a $40-$50 power supply. People might say they aren't that great, but I have put a couple in systems (including mine), and they've been running no problem for a long time. http://www.newegg.com/Product/Product.aspx...N82E16817148038
That Apevia looks very nice. I have an Apevia that is 500-watts with the same specs. Thats probably the new model. Also these Rosewills are pretty nice http://www.newegg.com/Product/ProductList....p;name=Rosewill
You can't crossfire your integrated graphics and your graphics card together unless your motherboard supports hybrid crossfire. That one doesn't, at least I don't think so. Also, you can't crossfire different cards together. If you are getting a 2600XT, you'll have to get another 2600XT to crossfire. It can be a different brand and have different clocks though.
"I think there is a world market for maybe five computers." - Thomas Watson, Chairman of IBM, 1943