DVD player 5.4 keeps crashing using a variety of DVDs.  I have OS 10.6.8, and have repaired permissions, verified the disc, and installed the 10.6.8 update combo.  Several previous questions have adressed this problem.  What is the solution

DVD player 5.4 keeps crashing.  I have seen here that a number of other people have had this problem.  I recently started one DVD, and when I went back to it, it opened to a black screen twice.  It also crashes with other DVDs after I scroll ahead or back.  It gives an error message that it is skipping damaged areas, or sometines error 69889.  Playing this on a PC, however, there is no problem.  I repaired the permissions, verified the disc, and installed the OS 10.6.8 combo update, all to no avail.  Techs told me that it is usually the hardware, so I bought a LaCie external combo drive.  Still crashes.  Looked on Apple downloads and they don't list a 5.4 to replace this version.  Mac informer.com offers a free download for DVD 5.5- should I try this?  Why doesn't Apple fix this problem?

Your suggestions did not help.  I repeated them again after the first try did not succeed.  Any other ideas?
Would installing another copy of DVD 5.4 help?  How can I get another copy of DVD player 5.4, since Apple does not seem to offer it?  I do have the disc for Snow Leopard, but am not extremely tech savy (and maybe it is the same corrupted version).