Many questions to be answered, im going to try to answer a few of them.

1. Aellie is 4x shaman, not 5. He is playing with a healer friend in the movie.
2. You Laptop might be able to launch 4-5 wow apps, but i doubt it will be a pleasant play so to speak.
3. Shamans (ele) are pritty gimped atm and not that good, not saying it wont change, just that they are weak at this time in wow.
4. Id recommend as u describe testing it out first (both for the computers sake and for your own), tho i can not recommend private server but trial accounts, and try out some questing and get a feel for the boxing program of your chooise.
5. Melee teams are pritty populair atm but id say that a shaman team would be easyer to understand and play.

GL.