the brand doesn't matter . the technical specifications Like CPU/GPU speed and RAM matter.
Like for instance, on my Laptop running windows I can get melee to barely run at 55-60 frames per second on less vibrant colored stages such as Battle Field and FD and here are my specs:
Intel Core 2 Duo 2.53Ghz w/ Integrated Graphics (this means my cpu and gpu come from the same source.)
8GB Ram
NVIDIA GeForce 9400M 256mb vram
To play On more stages you'd need a better CPU than what I have.
To check you're system Specifications:
Windows: Right Click on "My Computer" and scroll down to "Properties".
Mac Os X: Go to apple logo and click "about this mac" Then click "More Info"
If you're on linux I hope to god that you can figure out what your tech specs are.
Also, Dolphin runs better and is more developed on windows. if you have a mac try dual booting it with windows.
If you're still confused try googling what cpu, gpu and ram are.