What's wrong with my DVD-RW disc & joliet query

[celineg]

I have quite a worrying problem. I added some new jpg files to my 2007 photos DVD-RW disc using Nero Express. When I selected Add files, it did the usual of showing me what was on the disc already so I just added the files I needed to to burn them.

However, neither my cd or dvd drive will now recognise the disc! When I view the disc through Nero InfoTool, it says

DVD-RW
Capacity 2.34GB
Layers 1
Blank capacity n/a

Content:
File system ISO9660, Joliet
Title: 2007pix
Date 28 December 2007
Application: Nero Burning Rom

Have I done something wrong here? Can anyone help me somehow as to how I can actually get my pictures back, if indeed I have lost them somehow?

Any advice appreciated.

Thanks.