Replacing Vostro 1400 dvd drive?

I am thinking of buying a vostro 1400 from a friend and was wondering if it is possible to replace the dvd burner. He says that sometimes it work and sometimes it doesn't. Would this be an easy thing to do on my own? I want to put in a dual layer burner.

 

There should be just one screw on the bottom of the laptop that holds it in.

 

There is only one screw at the bottom of the computer, here is an image:

 

OK thanks. Now what should I look for in a new drive. Are most laptop drives the same? I want a DVD+R DL drive