Test print, What do I have to change?

I have had my printer (RepRapPro) up and running for a running for a couple of months now. I have read various articles and got what I thought were decent prints. I think I have everything set pretty close, but it´s not perfect, so I download this test piece from thingyverse and things didn´t go too well.








The measurements aren´t that far off, The square should be 140 x 140mm and my print is 140.00 x 140.00, so spot on. The circle is out 69.89mm and should be 70, it also isn´t round. The measurement I took is at the two points where it intersects with the cross piece. Where there is no intersection the measurements vary to a worse case of 68.60mm. The cube in the middle is just a mess, not cube like at all.

So my question is what do I have to do next to find out why the cube didn´t turn out too good. Then why the right hand side lifted. And finally why I get random layers that don´t stick too well as you can see in the pictures. It is not necessarily the bottom layer that is lifting, it is usually ok and nothing has lifted when it is 10 layers in, then things start lifting. I have the bed set to 65ºC printing 1.75mm PLA.