Playing burnt movie dvd's on my hp dv 5000

[Guest]

why cant I play burnt dvd movies I have made on my Dell xps desktop which play fine on my dvd player and my desktop my desktop is win7 and my laptop is XP Media center which is what came with my HP Pavilion DV5000 laptop I got it to work before and recently put in a new hard drive so I did a format and full fresh install the computer works perfect except for this WHY???????

 

[mhelm1]

Tell us what is happening? error on screen? no sound? won't load. what dvd format?