Dell laptop won't load past POST screen, no diag errors found.

Okay, I've got a bit of a weird one. The issue has progressed in stages.

-Last week, my computer was fine (a Dell Inspiron Laptop, running Windows 7, with a partition to run Ubuntu). I left the room, came back, and the computer was off. I turned it back on, and it blue screened. I loaded it into normal mode, ran CCleaner, and then attempted to run Malwarebytes. It wouldn't load at all. Tried to run a couple other virus cleaner programs. Nada. Wouldn't even say that it was loading. I would just click the .exe files and nothing would happen. From what I understand, it's likely a virus that prevents the opening of antivirus software.

I put the malwarebytes exe on a cd and a flash drive (using a file from another computer), neither of those worked. I tried all these steps again in safe mode, safe mode with networking, debugging mode, basically every option the advanced boot menu gives you. Zilch.

-After a day or so, my computer would only load windows in debugger mode. I should have backed up my files before this, but, alas, I'm an idiot.

So I went back to the beginning, trying to rule everything out. I reset the BIOS settings to default. I ran every single diagnostic possible, even the extended ones and the PSA. Everything. And absolutely NO errors were found. That took a couple days (have to go to work and sleep sometimes, ya know), and at this point, the computer had stopped even giving me the option to load any KIND of OS.

-Here's my issue now: the computer will load to the POST screen (Dell symbol, a loading bar at the bottom, and the F2 & F12 options. Tried F8, doesn't work). The POST will complete, it will move to a black screen with a blinking cursor at the top left, and immediately restarts. It loops this continuously unless you turn the computer off.

I unplugged every external device (mouse, usb, cd in drive), reset the BIOS settings again, ran diagnostics again, nothing will get me past the POST screen. At this point, I just want to get several important files and photos off of there, and then am happy to throw the laptop at the wall.

Can anyone help me?! Is there some tricksy, backdoor way of getting this computer nominally functional again so I can get those files and then do a factory reset? HELP!

Work through the steps for Troubleshooting Windows 7 Failure to Start starting with rescuing your files and then doing at least two of the bootable Virus scans including Malwarebytes if you can get into Safe Mode, attempt to repair system files from Win7 disk Command Line which is provided, then confirm Active partition and run several Startup Repairs, try System restore from Options list if it isn't offered.

After rescuing your files I would almost immediately run Dell Diagnostics from the F12 boot menu key to confirm the hardware. There may be a fuller suite on the choice for Utility Partition. If these will run then be sure to save the Utility Tools partition if you choose the superior Clean Reinstall - Factory OEM Windows 7 although all other partitions can be deleted.