your ram is DDR2 ... most new mother board use DDR3.... ram need upgrade
video card need upgrade too
microcenter have an upgrade mb/cpu combo for $99 ... most anything will be better than your setup ...
but what your PSU ?? that importance also
so with budget 150
mb/cpu = 99 Microcenter
ram 8 gig = 50-70
i would get by with that for now .. upgrade your video card latter
but the cost of cpu coooler be $30 too
i look at more like minimum of $200 include tax.