If you cant do anything,
boot the machine into safe mode and let Windows run chkdsk. While in safe mode, check the event log.
Control panel > administrative tools > event viewer > New window, in the top left expand Windows logs, let the lists populate.
In both the system and application categories, look for items tagged around the most recent bsod as warning or error. If it is a disk error, you will see controller or bad block/sector warning and chkdsk can temporarily repair them. If this is the case though, you need to get a backup going on essential data and send it back to alienware, take it to a shop, or look up a guide for your model laptop and replace it yourself because the drive is on its way out.
The only other culprit I would suspect is memory which you can test for errors with
memtest.
Also. Not sure if alienware has proprietary software for heat sensor monitoring, but ATI tool, ati tray tools, and GPU-Z can all give you sensor readings on your graphics card to check for overheating while coretemp can give you cpu and mainboard temperatures.
A good tip regardless of the problem would be to clean the laptop according to its specific model. If you google the model name and the word cleaning, there will likely be a guide on
disassembling and cleaning.