In the Control Panel
Select personalize.

Change the setting to 16 bit color instead of 32 bits colors.
Select advance, then it'll bring up more options. Intead of just using the slider bar.

Keep it at 60hrtz or above.
This is the flash rates, the higher the better, this will minimize headache if you stair at the PC screen for
a long time.

Also check in you BIOS, to see your Vidio card is set at maximun setting allow.
When you first trun on your PC...you'll see the F buttons or esc....(whatever your PC use to get to Bios.)
before Window loads.

For other window's settings such as the mouse, borders... select Window's basic color.
This has nothing to do with 16bit or 32 bit settings, but it'll free up your processor and vedio card more.

Scane through your start up programs. Depending what you've installed, some software
will automaticlly run everytime you trun on your PC..you won't even know it's running...just like anti virus software.
Disable these softwares....don't remove them just Disable them so they don't start automatically.