Social robotics is an emerging field that focuses on assisting people and facilitating their lives. Robot users might have different characteristics that affect the interaction, so personalising their experience in human-collaborative activities might improve and promote robot deployment in society. This paper investigates the effect of user demographic characteristics such as sex, age, occupation, robotics, and technological background on the interaction and user impressions on the robot. We measure and analyse user factors such as focussed attention, immersion, delight, enjoyment, and perception and perceived interaction and robot factors such as challenge, competence, reward factor, aesthetic appeal, and usability. Sixty-three participants interacted with the Mini social robot performing collaborative activities and completing at will some requests the robot asked them to complete. The results show that user characteristics such as gender significantly impact user factors like Focused attention, Enjoyment, or Delight, while others, such as Technological knowledge, impact Enjoyment or Challenge. Based on these results, we provide examples of adapting and improving the user experience in similar scenarios.