Hi Olga, also you may want to check out this recent message:
http://moi3d.com/forum/index.php?webtag=MOI&msg=1810.2

That has a short tutorial on another way to select objects that are inside of other ones by using the left-to-right window select, which only targets objects that are completely contained inside the selection window.

If things are getting in your way though, definitely hiding is a good way to deal with that problem.

Don't hesitate too much to hide things.

Also kind of a vaguely similar situation is if you are having difficulty targeting a particular point to snap on to, it is a good habit to get into to zoom in to make things easier on yourself rather than struggling with trying to work in an area that you can't clearly see.

- Michael