Thanks, bab2010, for your assistance! I was trying to save a new event to my iPhone's Google calendar. Just on a hunch, I tried re-booting the iPhone, and Voila! My calendar now seems to work as good as new!
I would like to use iCloud to sync my iPhone 4, but it confuses my iPhone when I then later try to sync it with my Contacts in Microsoft Outlook after I update those Contacts files on my PC. I have so much to learn!
I waited years to get this iPhone, and do not miss anything about my Palm smartphone, except for the text search function. Palm was slow but thorough with those searches. (Example: I forgot the name of my plumber, but I know that 'plumber' is recorded in the 'notes' field of the plumber's contact information - so with my Palm I could just search on 'plumber' and wait four minutes . . .)