Random and increasingly frequent BSOD's

This may be DirectX/video adapter related.

Follow the steps for Diagnosing basic problems with DirectX. To re-install your display card drivers as outlined in the DirectX link, use the following steps.

1. Download the latest drivers for your display card(s)
2. Click Start Menu
3. Right Click My Computer/Computer
4. Click Manage
5. Click Device Manager from the list on the left
6. Expand Display adapters
7. Do the following for each adapter (in case you have multiple display cards)
   
   • Right click the adapter
   • Click Uninstall (do not click OK in the dialog box that pops up after hitting Uninstall)
   • Put a tick in Delete driver software for this device (if this option is available, otherwise just hit OK) and hit OK
8. Restart your computer after uninstalling drivers for all display cards
9. Install the latest driver for the display cards once Windows starts

Alternatively:

1. Login as an adminstrative user
2. Download the latest drivers for your display card(s)
3. Click Start Menu
4. Click Control Panel
5. Click Hardware and Sound
6. Click Device Manager (the last link under Devices and Printers)
7. Expand Display adapters
8. Do the following for each adapter (in case you have multiple display cards)
   
   • Right click the adapter
   • Click Uninstall (do not click OK in the dialog box that pops up after hitting Uninstall)
   • Put a tick in Delete driver software for this device (if this option is available, otherwise just hit OK) and hit OK
9. Restart your computer after uninstalling drivers for all display cards
10. Install the latest driver for the display cards once Windows starts

Ok, I had to wait until today for my next Bluescreen, so I thought the problem had actually been solved. On the Bluescreen itself I noticed it read "MEMORY_MANAGEMENT" as a problem... Any clues?

That could be due to memory problems or a driver. Can you upload the latest crash reports?