Disabling V-sync, unless you having problems or you are trying to benchmark your system, is a silly technique.
Here's why...
V-sync llimits your frame rate to your monitors refresh rate. This will always be over 60fps, which is very smooth. Need more FPS? Most monitors do 85Hz at typical resolutions, which is fairly standard these days. So you are limiting yourself to probably 85Hz.
Many games have the option to disable v-sync. Also, if you go to Start / Control Panel / Display Properties / Settings / Advanced there will be an option to disable V-Sync using your video card's driver software (probably).
If you are getting low FPS, then you should consider other useful methods, like updating drivers, updating your game, lower detail settings etc...