It is not a very good idea to cover the whole window. Once the power goes off, not if it goes off, ventilation will be necessary. Besides the creature comfort issues, there are theories of leaving windows cracked to reduce major pressure differential between the inside and outside. Light is another thing, although candles are fun for a while.
Good point, ST. We cut handholds in our plywood to make it easier to handle. It also gives us ventilation and views to the outdoors. The handholds are about 2" x 8".
Most of the literature dissuades open windows--although my next-door neighbor swears by it. Just make sure the open window is on the leeward side of the storm, and be prepared to change when the wind direction changes.
Candles are a no-no during the storm. Too many fires occur when the wind breeches the structure.
With the kevlar screens, when they come, we'll have air circulation and light. I like the idea of handholds in the plywood. May well do that next time.
The farmer who hauled out the diesel the prior owner left here (in 55 gal drums) wasn't going to use it straight, but mix it with fresh fuel. I don't keep enough around normally, to worry about. I get 15-20 gals just prior to a storm approaching and then use it exercising the generator each month.