The song that Laura sings is "That's All I've Got to Say" from the animated movie, The Last Unicorn (1982).
Items in the time capsule include: an iPhone, a bottle of 5-Hour Energy, a can of Coca-Cola, a CFL light bulb, Fifty Shades of Grey (2015) (either DVD or book), an Adele album, a Snickers bar, a can of spam, over-the-ear headphones, a bottle of nail polish, cigarettes, a USA Today newspaper, money, a tube of toothpaste, Purell hand sanitizer, a tube of sunscreen, a stethoscope, a New York Yankees ball cap, regular glasses, sunglasses, a toy car, a Fitbit, a birthday card, a pair of flip flops, an X-Men: Days of Future Past (2014) t-shirt, a box of Oreos, a take-out pizza menu, a restaurant or diner menu, a video game, and a US magazine. There was also a small bottle of some sort pills, maybe diet pills or vitamins.
Tim Russ, who guest-starred as the historian (anthropologist/archeologist) Doctor Sherman, also played the Vulcan Mr. Tuvok in Star Trek: Voyager (1995), a terrorist in Starship Mine (1993), a lieutenant in Star Trek: Generations (1994) and a trooper in Spaceballs (1987).
Gordon, when told to "delete the holoprogram", says "everyone else has hooked up out here and it's my chance to hook up!" Scott Grimes, who plays Lieutenant Gordon Malloy, had just announced the week before that he and Adrianne Palicki (Commander Kelly Grayson) are engaged.
Gordon says he lost a bet when the simulated people question his uniform. This was the same excuse Picard used in The Big Goodbye (1988), the first story where the Holodeck was a primary setting. Gordon also refers to his outfit as pajamas, which was the impression the people of 1893 had of Data's uniform when he time traveled there in Time's Arrow (1992).