[herr-pear]

I'm going to make a statement that should offend EVERYBODY. IMHO the brand of equipment doesn't make a hoot as to how good a welder you are. Of course, parts & service should be factored in, as should availability of consumables and maybe even training.

Mig is the easiest to learn and use and will do most of what you want to do.
Tig is generally for real little stuff, stainless steel & aluminium.
Arc or Stick welders are generally for heaver sections although there is considerable overlap of useful thicknesses of metal with Mig.

I first learned Oxygen-Acetelyne welding and believe most schools prefer to teach that first. With A-C under your belt all the others come easily.

If you are going to teach yourself or have someone teach you on your equipment then Mig is probably the best way to go.

This advice is worth every penny you paid for it.