Alex

Problems i have right now, please someboedy help me! (my english is not very well, so sorry for that)!
So, my rig is:
MB: Gigabyte Z97X-Gaming 5
CPU: Intel Core i5 4690K @ 3.50 Ghz
GPU: Asus NVidia GeForce GTX 750 Ti Strix OC Edition 4096 MB/4.0 GB
RAM: Corsair Vengeance 8GBx2 @ 1600Mhz
SSD: Kingston 120 GB
HDD : WD 2 TB
OS: Windows 10 Pro, x64 version.
Monitor: LG 25UMM57-P, @ 2560x1080, 60 Hz
My 1st question is, how can i turn off the "Ultra fast boot" in this MB?
My 2nd question is: Why does GTA 5 not running at better quality for me like this:
My 3rd question is: How can i reach that normal functioning to play as a normaly, without laggs? How can i overclock the system?