I would just disconnect the HD from the logic board first rather than have to pull the LCD off to get to the HD. If it boots from the DVD and stays booted something's up with the HD. It may just be a matter of pulling it and putting into and external SATA case to see if you can repartition it. Do the procedure I mentioned above, but also in Security Options of Disk Utility do a one pass erase to see if all the blocks are okay and to put it through the paces for the whole HD.

Once you get the front bezel off there's no need to put it back on of course to check the machine sans HD, just put some RAM in.