An unencoded BluRay movie
will be large. 16GB is pretty small by my standards.
Watching videos shouldn't cause your system to crash - I'm wondering if something else is going on.
As a baseline - let's make sure we're on the same page for playback. You can either use VLC, or install the
LAV Filters and
MPC-HC. Either of those options will play just about any file you throw at them. Make sure that you've uninstalled any other "codec packs" that you have installed - you don't need them.
What are you using to rip the videos? I'd suggest installing
MakeMKV for now to get the content off your discs. MakeMKV is a very simple program that will take the raw data from your DVDs or BluRays, strip any content protection, and store the streams in an MKV file. Note: you'll have to disable AnyDVD while using it - the two don't play nicely together.
The output file will be large. For reference, my Gladiator extended edition comes in at ~35GB for just the video and a single English audio track.
Once you've got that file on your system, you should be able to play it using VLC or MPC-HC. If you've managed to cross this milestone, then we can worry about
re-encoding the video to save some disk space and make it possible to play back on multiple devices.