Considering the fact that the r7 260x is pretty power hungry, compared to the Maxwell architecture on the GTX 750 which allows it to run on an insanely low 55 watts TDP, I'd rather go for the GTX 750, which sounds like a great choice to me
assuming yo have a decent c2d cpu and at least 4gb of ram, a cheaper card such as the rx260x or a gtx 750-gtx 650ti would do you just fine (they are around 110-130 dollars depending what brand you choose)
Considering the fact that the r7 260x is pretty power hungry, compared to the Maxwell architecture on the GTX 750 which allows it to run on an insanely low 55 watts TDP, I'd rather go for the GTX 750, which sounds like a great choice to me