Laptop + External DVD RW drive

[WackityWhiz]

I have a Dell Inspiron 8600 with a regular dvd drive in it (i'm dumb and didn't spend the extra hundy on the upgrade). If I get an external dvd-rw drive, would I be able to put one of my dvds in my Inspiron and put a blank dvd in the external to make a back-up?

I don't know much about this, so any help would be appreciated.

also, which DVD's would be the best to use for this?

thanks,
-WW

*it sounds like it would work, almost sounds too simple. I just wanted to come here and clarify before I go spend money on it.