Unless there's anything which might get you into trouble with the authorities if found on 'your' machine, as you bought the machine on the understanding that it was a returned item I would just delete everything & forget about it.
Hands-on: Acer Predator Triton 700 review
1995-2015: How technology has changed the world in 20 years
This poetic animation about monsters is illustrated in a Van Gogh painterly style
Apple predictions 2017
Synology invites you to visit them at Insomnia on 26th – 29th August. Book your tickets now and visit Synology.