Movies Won’t Download

My friend tells me he has problems on his XP equipped HP whenever he tries to download or play an online movie in QuickTime, RealPlayer, Macromedia Flash (and maybe more). He gets crashes and program freeze-ups, requiring re-boots most of the time. Since he is in Williamsburg, VA., and I am in Buffalo, NY–with no direct access to his machine–can anyone give me a clue as to what might be going on? Oh, yes; he is at a very low-skill level re: technology; I would rank myself as “moderately skilled.”