Double click CD or DVD doesn't open folder

Hello,

I'm running windows XP on a dell d610 laptop. I have a USB DVD/CD RW drive and I also have a hot swap cd burner which plugs into the laptop. If I put a CD or DVD in either drive it will recognise the name of the disc but then when I double click it, nothing happens. It doesn't matter if they are both plugged in or just one it still does it. all other drives work fine including a USB external HDD. Hoping someone can help. Thanks