Playing DVDs on INSPIRON 1420

I need some assistance but am not sure if I am on the right thread.

I have loaded Roxio Creator and My DVD 9.0 DE several times over the last couple of years. I have NEVER been able to get it to function to watch a DVD( movie or other program) First I was told that it was a compatibiilty problem with VISTA so I found the patch and downloaded it. Then I am told that I have to buy another software to be able to watch DVDs. or upgrade to the 10.1 version. or Roxio 2009????  Is this true? I thought the MY DVD 9.0 allowed this to happen and it is why Dell put it into the package in the beginning.  So basically my Windows Media Player will not work to see a DVD without spending more money??? Also My original Media quick start program has disappeared off of the computer when I try to reload it I am unable to do it .  ANy suggestions?? ( the one you push that has the house on it???) Thanks, if I am in the wrong place please point me in the right direction. I just want to watch a movie on my computer now that I am in school it is essential.