turning my system on during lightning storms

Turn it off is the surest thing to do -- leave it on and you're inviting disaster (or an upgrade to your gear).

You would need to unplug the system in order to avoid lightening damage.

I'm no expert on electrical systems or lightening suppression, but I would think the most logical approach is a whole house surge suppressor installed at the meter by your power provider. That's what I'm going to do when we build our new house.

Enjoy,

TIC

Reubent is right. Turning your system off doesn't provide much protection. A lightning bolt that can jump several thousand feet of atmosphere is not going to be impressed by a gap of, at most, a few millimeters in your on-off switch. Unplugging you equipment is the best way to protect it.