[New Build] in need of advice and

Hello,
Building a new system for $1800 to play all games on ultra settings, It also needs to keep up with the new fibre internet here in AU, ATM i'm thinking of this build


Intel Core i5 2500(3.7GHz Turbo Quad-core)
GeForce GTX 670 2GB
1TB HDD
Gigabyte Motherboard
600W PSU
Samsung 24in Widescreen LED Monitor
G.Skill Ripjaws 16GB DDR3 RAM
Microsoft Windows 7 Home Premium
CoolerMaster Elite 430 Black with window

This is my first Complete custom build and was wondering what I could do to save a bit of money and improve performance
Thanks.