If your System Restore Windows takes a long time to perform, something wrong may happen with it or your PC. But you can wait for some minutes; it usually takes about 30-45 minutes to complete a system restore. And it can take up to 1.5-2 hours if your PC is running slow. If it is still stuck, there are some beneficial fixes to resolve this: run the SFC scan, try a different restore point and run System Restore in Safe Mode.