Hey Jackdied,
Are you A) actually editing all the 30 tracks or B) editing just some of them but you want to see all other tracks as a reference?
If A:
Why are you doing that? I normally edit just 1-5 tracks at the same time and when I want to edit more than one track I just select those tracks in the TV and then hit Alt+3 to open the PRV. And I use the Pick Tracks menu as necessary.
If B:
The only solution I can think of at the moment is you lock data of all clips that are on the tracks you don't want to edit before opening the PRV. Select all the tracks you don't want to edit and hit Ctrl+K (this will lock both clip position and clip data), then select all tracks and open the PRV. Now, in the PRV, there's no need to enable the Lock buttons of 29 tracks.
I hope someone else knows a better solution...