Won't play dvds (and how to play dvd's from laptop to television)

My Inspiron 6000 recently had to have the hard drive and motherboard replaced and I had to get new operating system and driver/software disks.....well they sent me the wrong disks...I've gotten it mostly figured out...but now I can't play dvd's....anyone know how to fix that problem?....i was also wondering how I can a dvd to play from the laptop to a tv...I got the s-video cable and the screen shows on the tv...but when I try to play a dvd the movie itself won't show on the tv screen (it does on the laptop...this is actually refering to a different laptop since I can't get this one to play dvd's at all.......but I figure it will do the same thing).  Anyway...I'd appreciate any help!