if i could spend more money i would go with this one http://www.newegg.com/Product/Product.aspx?Item=N82E168...
because i never know when i'll need the extra pci slots for something like a second graphics card or a tv tuner
but if you plan on keeping that build until you need to get a whole new set than you can stick with the micro-atx
OH VERY IMPORTANT
i forgot to mention that your graphics card requires a minimum of a 500 watt power supply and the one included is only a 450 watt psu
So if i get the fx 4100 how long do yu think that will last me in terms of games before i need to upgrade again?
I wantnto play games at high to ultra settings and i think my graphics card can handle it but im notnsure about my other components, what do yiu think?
An important(and probably the most broken) rule of building a computer is to never skimp on the power supply and you are breaking that rule. Its is very likely that power supply will fail in a fashion that will take some if not all of the hardware attached to it with it. Get a quality power supply from a manufacture Like Seasonic, XFX, Pc power and cooling, Corsair, or Antec.
It generally does get bad reviews. Partly because people compare it to Intel quad-cores (which cost far more) and partly because yes, it's not that great a processor. But at the £75 price range it's about the best available.
Trust me, it would be well worth your while to spend an extra £20 on the FX-4300 or even go with Intel and get an i3-2220. Of course that would require also changing the motherboard.