Laptop Randomly Locks Up!

Hello,

My Dell Inspiron M5040 (2011-2012) laptop randomly locks up without any error or noticeable reason. This issue started roughly two or three days ago. The screen will freeze, cursor won't move, keyboard unresponsive. Even system keys like CTRL+ALT+DEL does not work. I need to shut down the laptop using the power button for it to come back.

I tried calling tech support, and was walked through several steps. He first had me run the F12 Diagnostics which turned up no errors at all. After that, Windows brought up a screen where it was some sort of startup recovery. While "attempting to repair problems", it asked me if I wanted to do a system restore. The tech support guy told me to click yes, so I did.

As soon as I was finally able to log in after this process, I found that I was being denied permission to access my personal documents or programs. Certain folders and files were unaffected while others were locked out. the entire folder for Steam (a Valve Software program) was locked out, My Documents was locked out, Google Chrome was locked out, My Downloads was locked out. This permissions issue manifested itself as having the affected folders inaccessable to those programs (like Steam or Chrome), preventing them from even starting up.

After calling tech support again, I was told to go to System Restore again, and asked to 'undo' the system restore. The option was not available, only the option to restore to a date two days before I ever called Tech Support. After choosing that option, the system restore finished again. I logged into my windows account only to find that it was not actually my account at all anymore. It had my name and password, but ALL my personal programs and documents were completely missing, as well as my background and everything. These files and settings should have been there even after this system restore, since I chose a date only two days old.

A popup balloon informed me that I was logged into a temporary account, and that any files or settings would not be saved upon logging out. Frustrated with these results, I undid that system restore only to be brought back to the issue with file permissions. Tech support routed me to their advanced department.

Talking with their advanced technical support, I was informed that I only have a hardware warranty, and would need to pay $239.00 for a "software warranty" before they would help me any further. They would not even walk me through the steps to restoring the laptop to the factory settings. No further help was issued, only the offer for me to purchase that 12 month software warranty package. A smaller week long package was offered for about $150 give or take some tens. I declined both and hung up.

Determined to fix the issue on my own, I looked up Dell's online webpage for how to restore my computer to factory settings. After backing up my files and successfully resetting my windows installation to the Out-Of-The-Box state (factory settings), I was greeted within twenty minutes by the very same lockup issue that plagued me before. This made it fairly obvious to me that the issue is either caused by Dell's factory shipped software, or it is a hardware problem. The lockup issue was non-existent during the first two months of my use of the laptop, thus ruling out a conflict with the factory shipped software settings. Friends and forums have suggested it may be a bad hard drive.

My issue here is twofold:

1.) That my laptop has obvious lockup issues. Thanks to me resetting the device to factory settings, the permissions and account issues no longer exist. I have fixed those myself.

2.) That Dell's customer service refuses to assist me with an issue that could turn out to have nothing to do with software because I have not paid an exorbitant sum to them for a rudely overpriced 'warranty package'. Considering the steps taken above, it is almost certainly not a software issue at all, but I have little way to prove this to Dell without first paying for their ridiculous package.

So I turn to the forums, to make my case public to more than the outsourced customer service representatives. Does anyone have any suggestions for how to resolve this issue?