What RAM Should I Use On M5A97 R2.0 Mobo

Since it is new computer it'll have DDR3. What frequencies the ram support will be hard to tell without knowing the motherboard.
Most DDR3 motherboards support 1333MHz and 1600MHz.
If quad channel is supported on your motherboard go for 4x4gB memory if only dual channel is supported a go for 2x4gB(way better than having 1x8gB card.
Corsair, gskill, patriot are one of the best ram manufactures, so better buy any one from these manufacturers.
Provide your motherboard model number for more details

There is an easy way to know for sure. go to newegg and look at the details of the motherboard you are trying to buy.

http://www.newegg.com/Product/Product.aspx?Item=N82E168...

It supports DDR3 2133(O.C.)/1866/1600/1333/1066.

So something like this:

http://www.newegg.com/Product/Product.aspx?Item=N82E168...

I checked out your motherboard, and it shows that it uses DDR3 RAM, so I would recommend using a 1600mhz speed. As for type, its mostly just preference, and I tend to prefer corsair. One of my friends prefers Kingston. Since you asked, I would use this - http://www.tigerdirect.com/applications/SearchTools/ite... - its a corsair set that I used on a few builds that is very stable.

Thanks for the help everyone. I'm going with Corsair Vengeance

http://www.tigerdirect.com/applications/SearchTools/ite...

Unless someone has a bad review on it