Help! Pontiac Minivan Starting Problem!

We bought a 2001 Pontiac Silhouette minivan last week. It has power everything. We have discovered that some of the computerized features have to be done in a certain order. Here is the problem. I drove to town, came home, no trouble. Pulled the key partway out since I knew I'd be driving again shortly. Later, got in, engine wouldn't start. No battery trouble indicated, just silence. A couple hours later, same thing. All battery powered things working great, just won't start. DH tried his key, but no cigar. He attempted jump starting, but still no good. Read the manual, no help. I just signed up for AF today to ask you kind experts to shed some light on this very frustrating and mysterious situation. Thanks in advance,
Tinynedl