Snow Leopard-Blue Screen Reset PRAM Problem

Sorry, but you did not indicate in your post or profile what version of OS X you had installed.

Yes, they should be about the same. I think you will need to reinstall Snow Leopard:

Reinstall OS X without erasing the drive

1. Repair the Hard Drive and Permissions

Boot from your Snow Leopard Installer disc. After the installer loads select your language and click on the Continue button. When the menu bar appears select Disk Utility from the Utilities menu. After DU loads select your hard drive entry (mfgr.'s ID and drive size) from the the left side list. In the DU status area you will see an entry for the S.M.A.R.T. status of the hard drive. If it does not say "Verified" then the hard drive is failing or failed. (SMART status is not reported on external Firewire or USB drives.) If the drive is "Verified" then select your OS X volume from the list on the left (sub-entry below the drive entry,) click on the First Aid tab, then click on the Repair Disk button. If DU reports any errors that have been fixed, then re-run Repair Disk until no errors are reported. If no errors are reported click on the Repair Permissions button. Wait until the operation completes, then quit DU and return to the installer.

If DU reports errors it cannot fix, then you will need Disk Warrior and/or Tech Tool Pro to repair the drive. If you don't have either of them or if neither of them can fix the drive, then you will need to reformat the drive and reinstall OS X.

2. Reinstall Snow Leopard

If the drive is OK then quit DU and return to the installer. Proceed with reinstalling OS X. Note that the Snow Leopard installer will not erase your drive or disturb your files. After installing a fresh copy of OS X the installer will move your Home folder, third-party applications, support items, and network preferences into the newly installed system.

Download and install Mac OS X 10.6.8 Update Combo v1.1.

No, it can't do that. But sometimes it may fix the blue screen issue. I believe that is outlined in the first link I posted. But, as I said earlier, you will need to reinstall OS X to fix the problem you have.

Boot into the Safe Mode, then go to System Preferences/Users & Groups to add an account.

User Account – Add

User Account – Add New Admin

If the new account doesn't have problems, then the problem isn't a system wide problem. It is your current account.

OS X Yosemite- If you see a blue screen at startup

If it chimes when you hold down the keys, then the PRAM has been reset. Resetting your Mac's PRAM and NVRAM.

Startup Issues - Resolve

Startup Issues - Resolve (2)

Startup Issues - Resolve (3)

What happens when you start in a guest account (not safe mode)?

That's what it does unless you release the keys.