Hey there, Rafael!
Unfortunately, just like @rgd1101 mentioned, it's not uncommon for a non-system drive to affect the performance of your PC like this. I'd strongly advise you to attempt to plug the HDD externally via SATA-to-USB cable (+ an adapter) or a docking station. This will allow you to, hopefully, access your data and back it up before it completely fails. Besides, it will allow your system to boot properly without the drive interfering with the boot-up process.
I'd also recommend you to check the health and SMART data of the drive using its brand-specific diagnostic tool from the manufacturer's website. If it still affects the system poorly, you should create a bootable flash drive with the DOS version of that HDD testing utility and check up on the drive without booting into Windows.
Keep us posted & Good luck!
SuperSoph_WD