with reference to the vignetting (dark endges), this is likely that you are using your old crop sensor lenses on full frame camera, this is because the lenses are designed to focus the light onto the smaller DX sensor (crop sensor), so they wont cover the larger FX sensor (full frame sensor) causing the dark edges, to avoid this use the camera in c1.5 crop or DX mode with those lenses and acquire some full frame lenses will stop this.
the photos being blurry in burst mode or when taking photos in quick succession could be down to the fact that the autofocus has not had time to aquire a lock before the shutter fires, try using rear button focusing or changing the release priority or focus rather than release...