I am only gonna hit some of the highlights, but among the top is I got to see The Who with Keith Moon in '75 on the Who by Numbers tour. It was awesome. I have seen The Who 4 times and another time was the 25th anniversary of the Quadrophenia album in St. Louis. They played the whole album (my fav album of all time) plus 5 songs after it was over. A great show.
I have seen JTull twice, but the best was his solo Rubbing Elbows Tour a couple of years ago in a small theater with great acoustics. If you ever get to see Ian in one of these settings, GO! he does interviews and Q&A in between songs.
I was at the first Texas Jam circa 1978. Started at 9am and ended at 2am. I can't remember everybody that played, but here's what I can rememeber, other than it was extremely HOT. Van Halen, Aerosmith, Ted Nugent, Walter Egan, Heart, Mahogany Rush, Eddie Money, Journey, Head East and others. Looks like they are getting to release a movie about this also.
http://www.imdb.com/title/tt0460957/
Also the Marillion concert I went with Vaxman and Mrs. Vaxman and Nadina in San Francisco of this year Sept 11th, 2005. A night I will never forget.
The Supertramp concert in Norman, OK circa 1978 or 79.
And the first time I saw Ozzy with Randy Rhoads. The Diary of a Madman tour. I went to my night class and they were giving a test and I didn't know they were. We could drop the lowest grade, so I left the class, wrote a hot check and drove 90 MPH 45 minute drive to go to that concert.
I'm sure I'll think of others later, but these are the cream of the crop.