The 1250 should do fine for WoW and very very light gaming. Its an integrated gpu which will steal resources from other parts of your computer. If you can spend an extra hundred or so go with a midrange 8600 or 2600 card.
Its not bad. As mentioned above, it beats the heck out of any intigrated intel chipset. Pair it with a gig or 2 of ram and you should be able to play wow around medium settings.