A few things I can think of: There is a troubleshooting document available here. Some Blu-ray media requires updated decoder software due to encryption. To get that you'll need to update your blu-ray movie playback software. There should be an update feature/option in the software. As for the other media, have you tried it in other drives?
yes. I also have an hp pavilion dm4, i5 cpu, m 430 @2.27g, 4 g ram, 64 bit os. Every dvd/cd i have problems with on the envy, I try on the dm4 and they work fine.(except for the blu-ray, I try that on a home plyayer)