If the discs are skimmed up on the car then it will fix your run out problems and the vibration will go. However, having said that be very careful skimming can hide underlying problems, such as a wheel bearing on the way out or a bent hub. I know I have a bent hub on mine, back left. After getting the hub off and measured on the CMM at work two "lobes" on the hub were 0.1mm lower than the other 3 so the disc sits wonky on the hub thus runout was about 0.4mm at the edge of the disk. Ideally you want as close to 0 runout as possible, but less than 0.07mm at the back and 0.05mm at the front is acceptable on the Brembos.
In my experience its not usually warped discs but has been caused by discs not being fitted correctly.
It is essential when changing disks to check the runout of the disk with a proper DTI and make sure run out is in spec.
A way to check how many of your disks are running out is drive around for a bit, stop and feel your disks. If any differ in temperature from the rest they are running out for some reason. Either warped or not fitted properly.
One thing to be wary of is that when they skim your disks they don't take them too near to minimum disk thickness because then they will warp due to thermal stresses and possibly crack. Additionally if skimmed near minimum thickness the temps can cause microstructure changes in the disc material causing hard spots to form which don't wear down as the rest of the disc does and then the vibration comes back.