AOL Releasing 5.0

America Online Inc. is set to unveil today the latest software upgrade for the more than 18 million members of its flagship Internet service, with new features for Web searching, posting photos online, home-page personalization and online events calendars. In what is becoming a fall ritual meant to capitalize on the upswing in home Internet use after the summer months, AOL is distributing millions of copies of AOL 5.0 through mass mailings and as print media inserts.