Best S/W to make slide show with music?

I have about 2.5 gb of best of photos of our 23 day John Muir Trail hike (we had 3-5 photographers on the hike) and would like to make a slide show with cool transition effects plus background music and the finished show can be shown on a TV. Do you have any recommended Software. I'd like to upload it to You Tube too, but in a manner that does not get the copyright cops after me — I like http://tinyurl.com/yc343gp (click on some of his JMT videos). With his back ground music, options come up to click on amazon and buy the music — so I bet no copyright cops are upset about use of the music. Only thing missing in his slide show is the lack of transition effects which I find cool.

Any recommendations — what have you used?