BSOD Multiple Firefox Tabs Error Stop 0x0000007A

My laptop was left on yesterday with numerous firefox tabs open (x20) for various websites, although no one was using the computer and this is a regular occurrence without fault until yesterday. I'd gone out fishing and noticed the BSOD and took this photo of the screen showing the full error as "stop 0x0000007A (0xc0487688, 0x3e5898c0, 0x96ed7e3e)"

I had altered the BSOD settings in the past to stop the laptop from restarting in order to have time to take note of the error codes in case of future failures, although I hadn't had any BSOD for over a year. The previous BSOD's were 0x000000d1 (netwLv32.sys) and 0x0000007e (Volsnap.sys), unlike those BSOD's, the one shown in the photo doesn't have a description other than the error code.

I had turned off the laptop while in BSOD, having completed dumping physical memory; subquent restarts were only reaching here followed promptly by a black screen with the flashing white underscore, which I could escape by alt+Ctrl+delete. At one point the laptop did load and somehow I was able to access System recovery options and selected startup repair, which I viewed the log prior to restarting and everything completed successfully and although I did restart the computer, I haven't been able to proceed further than the initial loading window or the defaulting black screen that follows.

I've tried running the BIOS setup utility, with the hard disk self test diagnostics, though this failed each time.

Not able to provide any debug logs until I can proceed further. Have the windows 7 back up DVD disc, but not sure if my DVD drive is playing up, as when I push ESC and enter into the boot menu selecting the Atapi cd/DVD rom drive, it only goes to the prior mentioned black screen and remains there long after 5 mins. The disc drive is heard to be working if the disc is within, though nothing results on the screen. I had recalled some difficulty prior to this BSOD with the CD/DVD rom, having decided it was either only a driver or possibly registry error or required itunes reinstall, as afterwards having successfully read a music cd with itunes.

I don't think I have the windows recovery discs or system restore discs, as I tried some I thought were these, but nothing occurred and I figure they must be from when I tested the windows 7 beta or W7RC or such. So only have the legit Windows 7 back up disc (32 & 64 bits), which I was running 32 bit. Only twice has it shown up "Press any key to boot from disc", although there was no response and it doesn't always reach this prompt.