LIBSVM is a great tool for performing SVM based classification (or regression).
It supports MATLAB, so I think you'll find it useful.
But since LIBSVM doesn't scale up to a large dataset, it might take long depending on the dimensionality of your data and your environment.
(although you can make it faster by turning on or off the shrinking heuristics option -h, theres no general rule for it)
In that case, I recommend you to refer to this post: