Help with resolving GLX and dependencies

[aki]

Recently when I tried to do a YUM update my YUM wasn't able to resolve these dependencies....

Resolving dependencies
.Package vcdimager needs libiso9660.so.0, this is not available.
Package vcdimager-libvcd needs libiso9660.so.0, this is not available.
Package vcdimager needs libiso9660.so.0(ISO9660_0), this is not available.
Package vcdimager-libvcd needs libiso9660.so.0(ISO9660_0), this is not available.
Package vlc needs libdvdnav.so.0, this is not available.

Could it have anything to do that I update my kernel??

Also I am not being able to run glxgeras... I keep on gettign this mssg

[agarwal@localhost agarwal]$ glxgears
Xlib: extension "GLX" missing on display ":0.0".
Error: couldn't get an RGB, Double-buffered visual

Any suggestions. Thanks.