Problems playing some DVD's

[Zyraki]

I have a Panasonic DVD-A160, and it appears to not want to play some DVD's. All the disks are region 2, and some of the disks will play and some won't. For instance Black Hawk Down is a 2 DVD set, my machine will play Disk 2 (the extra features disk) but not disk 1 (the main feature). Any ideas? or is my machine screwed?

[SKD_Tech]

Do other Region 2 DVD's play in your rom?

[Zyraki]

The majority of region 2 disks work, but some of the others don't.
i.e. Ice Age & What Women Want.