When Kristen Vallaire brought home a used Sony DVD player she’d bought at a Goodwill in Leland, North Carolina, she expected it to power on to a blank screen. Instead, when she hooked it up to her TV on May 12, it started playing a stranger’s wedding. Someone had left a DVD inside and forgotten about it. Most people would have ejected it, shrugged, and moved on. Vallaire decided the couple in the video should have it back. The problem was that s…