The Dell Inspiron from Hell

While my Lenovo is with the Geek Squad-and probably not coming back based on a rather grim prognosis, so Lenovo's warranty system better send me a replacement, or I swear-I'm trying to use my Mom's old Inspiron. I knew she'd kind of beat it up, but...Holy shit, man. Holy shit.

All I was trying to do was uninstall some old programs so it would run better, like the stupid UltraAV, which I'm pretty sure was what finished off my own old Inspiron. I also got rid of some old unused games, the Adobe Acrobat suite, and Netflix. Nothing that should have messed up the internal Windows files. Somehow, running UninstallR to perform the cleanest uninstall possible, which never caused either of my laptops any of this grief, caused the system to actually forget what the login PIN was. No joke. According to the troubleshooter, something corrupted some internal files. And the troubleshooter couldn't repair those files when I tried. So, off the bat, that's not normal. 

It won't let me add my own account from the login screen. Microsoft says I can do it from the command prompt if I run from Safe Mode. Fine. Unfortunately, booting into Safe Mode doesn't work. I hold down F4. I hold down Alt + F4. I hold down Fn + F4. I hold down Alt + Fn + F4. Nothing boots into Safe Mode as it should. I try powering it all the way off so I can try a complete reboot. The computer can't even do that. It just jumps straight back to the login screen, even if I hold the power button for a good ten seconds. I can't run the command prompt from the troubleshooting menu because that requires the login the system forgot. Can I reset the PIN? Not without the security tab thingy that she probably threw out or lost in her junk drawer.

So, the only option I can think of is a complete factory reset. But I'm frightened of the idea that this laptop's data and my mom's current one are actually shared, so performing a reset on this device with also wipe everything off the current one. You think that's irrational, but my mom absolutely would rig it that way if she could. Or at least rig it to alert her if someone tried breaking in to the old laptop.

Please remember that I got completely locked out of the system with no way around it all because I uninstalled some useless programs. How do you get a Windows install so broken down that trying to uninstall things gets you completely locked out of the system. I know my mom never let this laptop shut down all the way, ever, she just kept it in an eternal state of sleep, but that should not be enough to corrupt the files this fucking bad. If I can't figure something out, this thing is now just a paperweight.