Is there a way to lock tracks in place?

Locking the tracks (which is easy) is probably a bad idea at this stage. The reason is that if you decide to cut something out of them, the remainder of the track will also be locked, and you won't be able to close up any gaps...

If you've got two synchronised tracks that you want to edit, there's more than one possibility. Firstly if it's two mono tracks you could combine them into a stereo track and just edit that. Secondly, you could do what I'd probably do - which is to group both files, select the 'Razor all clips' setting on the Razor tool and make your cuts across both clips simultaneously. You will now find that each cut creates a new group after the cut. As long as you don't lock any of these in time, the individual groups can be slid around with the Move tool. Because the groups are automatically synchronised, nothing will move out of relative place when you move them.

If you think that's too complicated (it's actually pretty easy when you get into it), then go for the first option. Locking the tracks though - not good if you want to edit them! If you really want to experiment with this, then the track lock menu option is just a right mouse click away when you've selected a clip or file. You'll find that there are a lot of other options there too - often overlooked!