Disappearing DVDRW Drive

Hi, this is my first post here so bare with me if I'm not all that up to speed.

Anywho, I have a HP Pavillion dv9000 laptop and recently I've found that my
DVDRW Drive tends to disappear (both from the computer and device manager)
after a random amount of time.

This is nearly always tied to my usage of Windows Media Player or iTunes 7.
I am leaning towards a compatibility issue with iTunes but would that be able
to make my drive disappear completely? Putting my laptop to sleep and waking
it up usually revives the drive, as does a reboot. I'm more than annoyed with
it right now.

Also, when I have my printer and ext harddrive (wd MyBook) connected to my
laptop and I put it to sleep, vista tends to fail to load and I have to
reboot when I try to wake it up. Is anyone else experiencing these problems
or is just me (as it seems to be in most occasions)?

Any assistance would be greatly appreciated.

Thank you!
--
~Gaelen Kerr