to get the data off of it, you could try taking the hard drive out and hooking it up to another computer. I'd guess that its a SATA hard drive and the easiest way would be to get an external enclosure or a SATA to USB adapter. or if you have a desktop, you could hook it up internally if you have another SATA cable.
once it's hooked up, windows should see it automatically and you can browse the files on it and backup the files you want too.
As for the hard drive though, sounds like it's a bad drive, but Dells diagnostics are not as good as some others out there, but they won't replace a drive unless it fails their test. I might try an online chat with them or call them again and try being assertive with them, they will replace the drive usually, just need to be tough with them.
once it's hooked up, windows should see it automatically and you can browse the files on it and backup the files you want too.
As for the hard drive though, sounds like it's a bad drive, but Dells diagnostics are not as good as some others out there, but they won't replace a drive unless it fails their test. I might try an online chat with them or call them again and try being assertive with them, they will replace the drive usually, just need to be tough with them.