Unless cared for in the real world when playing Better Than Life, a Game Head dies very quickly. While it is certainly possible for friends to forcibly remove the headset that contains the game, this results in instant death from shock. The only way to exit the game is to figure out that you're playing the game, develop the desire to leave it and then command an exit.
A game head woman and her Bliss addicted boyfriend appear early in the first novel, with her only surviving thanks to the care of her lover. The notes on Better Than Life provide a prologue for events later in the novel and the boyfriend also mugs Lister for money to buy Bliss. This helps Lister make his decision to join the Space Corps in the hopes of ending his exile on Mimas and return to Earth.
Dave Lister, The Cat, Arnold Rimmer and even Kryten temporarily became Game Heads in the novels Infinity Welcomes Careful Drivers and its sequel Better Than Life. The Cat is the first to stumble into it, while celebrating the revival of the Nova 5 with the others (and the possibility of using the ship's Duality Jump drive to return to Earth). Lister then goes into the game trying to rescue him, even though he knows of the game's powers (he was drunk after all), and soon falls victim to the game's ability to make users believe they are in reality. Finally Rimmer goes into the game and is similarly afflicted. Kryten, after long cajoling from Holly, forces himself to burn warnings onto Lister arm in attempt get them to realize the danger. When he thinks this does not work he enters the game himself.
Even though they all knew now that they were in a lethal game they were too addicted to leave, including Kryten who had fallen for the amazing cleaning opportunities first at a imaginary diner and then in the castle of Cat's fantasy. Only after Rimmer's inner self-loathing manifests itself into his and the other's fantasies do they finally leave, with the Cat and Lister incredibly weak and feeble which leads to a long and turbulent recovery. The games first came onto the ship in the hands of Petrovich, a successful up and coming Second Technician and Rimmer's old adversary to promotion. The rumours that were spreading across the ship (with help from Rimmer) of him being an illegal Better Than Life smuggler were true.
In the terms of the Backwards sequel to the novel Better Than Life, Lister and the Cat use the Wildfire drive to enter another dimension where they find the others (Rimmer, Holly, and Kryten) alive but them having died in Better Than Life. This turns out to be a stroke of luck as the others were all dead from the Aginoids in their reality.
Within the hallucination (and thus a parallel reality following Back to Earth rules) created by the Despair Squid as its form of attack in the Series V episode "Back to Reality", there are massive video arcades for Total Immersion Video Games. The most popular game is, Red Dwarf, a simulation of the crew's actual adventures. Awaking from the illusions with some memory loss, or so they think, they awake to a world where they have different and inherently worse identities. They also proved pretty pathetic Game Heads as they missed most of the best bits and only scored three percent. The machines are monitored by a Brummie technician named Andy. Withen the episode another set of Red Dwarf "crew" are encountered, and prove far more successful in the game than they were.