[CRASH] Toshiba Laptop Will Not Boot

I have a year old Toshiba laptop that just stopped booting up this week. Worked fine Sunday, then Monday it would not start. Black screen with the option to repair or start normally. Repair goes through the motions and then states it was unsuccessful. Starting normally will eventually reach the desktop, but nothing will function at that point. The pointer is in perpetual hourglass when held over the task bar. Nothing, such as Explorer, will start.I pulled the hard drive out and connected it to another Win 7 computer via SATA/USB cable set. Initially, I could see the drive and access the files. Foolishly, I chose to run an antivirus before backing up the files. I was concerned about backing up the potential problem. MalwareBytes did not identify any malicious files, but Semantic threw up a warning about Yontoon-S.exe, so I attempted to delete it via Explorer. That action locked up Explorer. I rebooted the host computer. I should have backed up first because now I am unable to see the files. Explorer will assign the drive a letter, but when I select the drive to do anything, Explorer thinks about it for some time and then puts up a message that the drive must be formatted before it can be used. I do not want to reformat until I recover my data first. I tried to use SeaTools to diagnose drive problems. Drive fails the short generic test. I am not able to run Check Disk because Explorer thinks the drive must be formatted first. How can I get to the data before reformatting?