For casual gaming and the occasional AAA title is an i3-4130 enough?
The main use of the PC would be for surfing the internet so I'm not looking to spend much after my overkill rig.
Would it also bottleneck a GTX 750Ti?
The i3 is a great CPU, you wont regret one.
The current i3s perform somewhere in the area of the FX 6300 and FX 8320 for gaming performance. You could go up to a 770 probably and most games won't see much of a difference between the i3 and an i5.