First off, welcome fist time poster!
But, no ones gonna answer this question.
Its due to no fault of your own being a first time poster.
First you should take your time to read through the FAQ listed at the top of the main wow forum. It will help to keep you from asking questions that have been asked a thousand times.
Also, you may one to read through the FAQ on the trade skills board too, it will keep you from asking those questions as well.
Including this question, which is the first best class? Every class is good.
If you want a break down of which class does what, well the faq or there are hundreds of threads already posted on the topic. :)
Here's an answer to you question, dont worry. No matter which class you choose you will love it. Pick one based on which playstyle you think would be fun to play.