Boot problems on my world book II

all of a sudden the bottom light comes on hangs for 18 seconds then moves up through the lights then after a few time just hangs on the bottom light  re booted it and nothing.

I moved all my information over to this drive before reinstalling windows and im in fear I will have lost everything if the drive is faulty.

ok so I have left it for a good 30 min the full strip of lights is on then fades out fades in then out thats it still no access