I have a Compaq CQ50-215CA laptop and after a year and 5 months, the screen is completely distorted now. I plan on removing the screen soon, but I realize that the BIOS screen, OS select and Vista boot sequence are all displayed on the laptop screen rather than the external display. Is there some way to get the laptop to display everything (From boot-up to shutdown) on an external display (VGA port)?
There is either a mechanical or magnetic switch that is activated when you close the screen. Find this switch.
Once you've found it, change your OS settings so the laptop will "Do nothing" when the laptop is closed (i.e., when the display is folded down). In Windows, this is in the Power Settings control panel. Once you've done this, permanently activate the switch by taping/gluing it down (mechanical switch) or by attaching a small magnet over the switch (magnetic switch).
The laptop will now always be in "external display" mode.
Locating the display switch
Note that the switch could be in the hinge gap between the body and the display of the laptop, if it's a mechanical switch. If it's a magnetic switch, the magnet will probably be in the display's bezel.
If you can't find the mechanical switch and you don't plan on using the laptop display anyway, you could just completely remove the display from the laptop and dismantle the display to find the magnet.
Another option: actually fix the display
Another option would be to try replacing the video cable for your laptop. This will cost you about $20 to try, so you'll have to decide whether it's worth it for you. If it works, great! One of my friends was able to successfully replace his two or three times. If you can get the display to work better or worse by wiggling the screen (or if you used to be able to, but the situation worsened), then replacing the cable will probably fix your problem.
However, it's also possible the defect is with the LCD panel or other electronics. My brother had a display on which the lower third of the screen just stopped working (it was always black). We tried replacing his video cable, but it didn't work in that case.
Lifehacker has a very nice feature article on DIY Laptop Screen repairing or going headless...Looks good, has video and photos...