Quote I have my main storyline videos on track 1 and B roll on track 2. When I change the speed (length) of a video on track 2 it inserts a space and moves all the videos on track 1, which I don't want to happen.

Thanks

You have options to not move track, move only one track, or all tracks.
You can also lock the track by the lock on the left side. See picture.

Quote I have my main storyline videos on track 1 and B roll on track 2. When I change the speed (length) of a video on track 2 it inserts a space and moves all the videos on track 1, which I don't want to happen.

Thanks

Another option...........In order to fill that gap and bring the other clips back in sync, hold down your left mouse button on an empty track on the timeline and then move your cursor. You will see a box start to emerge. Every clip that that box touches will be selected. You can then move all of those selected clips at the same time to fill your gap.