(DVI = HDMI) > VGA
VGA isn't as good in quality picture, and more dependent on a quality shielded cable: otherwise you'll lose sharpness.
Basically VGA is fine, but if your PC has HDMI, I'd suggest you use that. DVI is actually a connection that I've never used, but since it's technically equal in signal quality to the HDMI it's also a good option.
In the end, all 3 are going to be fine, just make sure that when using VGA: you aren't using a low-quality "pencil thick" cable, you want it to be 2-pencils thick.
No matter which connection you choose, always calibrate the TV afterward, checking-and-rechecking every option for optimum picture quality.