Well I am cantonese. I want to speak mandarin. I am very fluent in cantonese. Since I'm a cantanese person will i be able to learn the new language a little bit faster. My friends told me i have the accent of mandarin so i am planning on learning the language. Which is better Rosetta stone or Pimsleur Approach

ok well apparently the languages are similar, so there shouldn't be a problem there. But what ever you do, don't do 'language programmes', especially Rosetta stone or Pimsleur. My best advice for you, is to go and meet mandarin speaking people. Even go and get a job in a Mandarin speaking environment. The quickest way to learn is by being in that environment. (That is the way we all learn our first language). Also get a dictionary and try to learn as many words as you can. There is also a website, which is very useful.
http://chinesepod.com/
It has lots of pod casts, which will help you with your pronunciation.

Good luck.

you should be able to learn mandarin easily. cantonese is one of the closest dialects to mandarin so i dont see a problem. if you're ok with learning by yourself, its fine, but i think taking a class would be a better experience.

I'm cantonese too!! honestly though, i never succeeded at learning mandarin, i tried by watching the movies my sister watches to try to learn, but it just wasnt possible (my sister somehow came to be able to understand but cant speak madarin), and i doubt that some american software can help me learn it. though its nice to meet someone thats cantonese too! i would like to hear from you and be friends. ??!

I took Mandarin class with many native Cantonese speakers. The youngest, at age 12, picked up the Mandarin vocabulary quite easily and spent most of his time working on the Mandarin accent. My husband's family are primarily Cantonese speakers, and tell me that Mandarin uses more "sh" "x" sounds than Cantonese. It should come easily to you if you work more on your accent. You'll need to practice on curling your tongue to the roof of your month to get the differing sounds.
You are better off learning in a classroom environment where an instructor can correct your accent and so you can practice with other students which is most helpful. Good luck! ;o)