The 760 is more powerful than the 750Ti.
A great cheap monitor is this one, but I don't think you'd have enough money left over between the 760 and 750Ti.
I'd go for the 760 and save up for a new monitor personally, but the 750Ti isn't a slouch, especially at your current resolution.
One thing to keep in mind is the 760 supports a sli configuration (dual cards) so in the future if your building a system or upgrading your mother board you can also purchase a secound 760 and use both.
The 750ti doesn't support that I believe.