First, the technical stuff. In the great commission and in Acts 2, the word that they use for baptism is the same, and does mean to submerge in water. They are derived from the word that means to make moist. The story in Acts 10 doesn't specifically mention Cornelius as being baptized in the Spirit before by water, but it does say that the crowd fit that category, so it doesn't really defeat the point. Either way, Cornelius was obviously pleasing in God's sight before he even talked to the angel.
Now, the stuff that matters. The more I study this topic, the more I understand our faith to be a smooth progression as opposed to a series of mountaintop events. When did we ever read that the disciples made a 'declaration of faith' similar to our sinner's prayer? Not to say that our North American method of praying for the first time is bad, but more that our faith isn't this nice cookie cutter program where one event lines up nicely after the other.
The NT makes consistent references to belief and baptism together. Baptism did not occur months or years after a profession of faith...it happened right then and there.
It is obvious that the order of 'baptisms' is not important...or at least as not as important as we make it out to be.
There seems to be a distinction between the gift of the Holy Spirit and the gifts of the Holy Spirit.
I think that the gift of the Holy Spirit implies the gifts, but like anything else in our faith, we must seek them out, ask for greater empowering, etc.
Some folks have had that mountaintop experience where there was baptism in the Holy Ghost, speaking in tongues and all the rest. I happen to be one of them. While I don't agree with the theology of how it all came together, that experience is not in any way diminished. God used that event in spite of me and the people with me to lend me greater empowering and revelation in the Holy Spirit than I had before. It was REAL...which I guess is what matters.