CarCrazy98,
If it is only firefox causing the system to freeze you may want to uninstall and reinstall it to see if that helps. You may also run the diags on the system by following the information below.
Turn on or restart the computer.
When the Dell logo appears, press immediately. If you wait too long and the operating system logo appears, continue to wait until you see the Microsoft® Windows® desktop, and then shut down the computer and try again.
When the boot device list appears, highlight Boot to Utility Partition and press .
When the Dell Diagnostics main menu appears, select the test you want to run.
If nothing is reported as failing you can always Format and Reinstall Windows.

I will go ahead and run the diagnostics in a little bit. I don't think it's isolated to Firefox, because I was using it the other night and going through documents and I opened a few PDFs and Adobe was not opening, and when it did it froze up in the same manner as Firefox. It may just be a coincidence, but with the issues I've been having, I don't think so.

Please refer below fixes, methods & instructions which might resolve your issue::

Quick fixes for Windows 10 computer freezing randomly

Fix#1. Free up disk space on system disk

Low disk space on system disk will slow down PC and even cause random Windows 10 freezing issue, so first, please make sure that you have enough free disk space on C drive. If not, you can try to clean up junk files to free up some disk space using Windows 10 disk cleanup. Or trying another better solution - to extend system drive using EaseUS free partition software.

Fix#2. Disconnect All Devices

Disconnect all external USB devices even including the mouse and keyboard from the computer and then boot up to check if they are the causes of random computer freezes.  

Fix#3. Check for faulty hardware 

Damaged hardware is one of the factors that can trigger computer freezing issue. But if the issue only happens in Windows 10, we can confirm that there is nothing wrong with your hardware.

Fix#4. Uninstall Incompatible Programs

Did you install any new programs before your computer freezing? If yes, it might the problem. Please try to uninstall them to see if it helps.

Fix#5. Scan with SFC to repair corrupt system files

Random hangs & freezes on Windows 10 sometimes happens when system files get corrupted. To test and correct it, run a Command Prompt as administrator, in the black Command Prompt window, type: sfc /scannow.Then press Enter on your keyboard. 

Advanced solutions to fix random freezes on Windows 10 computer

Getting tried of trying all these general methods one by one but none of them is useful? If yes, advanced solutions are offered in the next part to help. Please have a try!

Method 1. Updating all device drivers to the newest 

According to users, random computer freezing usually appears after Windows 10 update. And the reason might be incompatibility of hardware and drivers. To correct it, just update all device drivers.

1) Click Start menu and click Settings tab.
2) Click Update & security.
3) Select Windows Update in the left pane and click Check for updates (make sure you have an active Internet connection).

Method 2. Flash your SSD

If you have Windows 10 installed on your SSD, you might experience random freezing on your computer due to older firmware. To fix it, just install the newest firmware on your SSD.

1) Open your advanced power plan settings.
2) Expand open Hard disk and Turn off hard disk after, SET TO NEVER, and click/tap on OK.

Method 3. Perform a system restore or a clean install of Windows 10

If your computer still freezes frequently and randomly on Windows 10, you may try to either perform a system restore to roll back to the previous version or do a clean install of Windows 10 to find a fix.

I ran through the diagnostics, and everything passed just fine. I've run it before, but I will run another SFC scan.

This is Windows XP by the way, not 10.