The i3s are basically the same. In games that those cards can handle, I'd rather have the 750 Ti. It's an actual gaming card, whereas the 1030 is really an integrated graphics replacement.
Just don't be unrealistic in your expectations. Neither of these computers is entry level for gaming, much less mid range. A quad core with GTX 1050 would be entry level, these computers are a notch below that. Even so, there are still a lot of games you will be able to run and enjoy.