Context gives a lot... the Radeon 7500G is not the same as the Radeon Mobility 7500. The 7500G is from the Trinity APU series and clocks up to 424Mhz with 256 pipelines (as opposed to just 2). It should be capable of all light gaming.
The CPU however is not very strong at all. I remember reading that PS2 emulation needs 3Ghz minimum, and the A6 only does 2.1Ghz, not to mention that AMD has far less IPC than Intel so 3Ghz from Intel gets much more done than 3Ghz from AMD.
I don't know for GameCube emulation (never tried, I have a Wii for that) but handheld emulation should be fine.