The end Zizek is aiming at is to raise consciousness in the general public that they can act in ways that changes things. Its why he is in the media a lot, and why he does a lot of film criticism. Check out his DVD The pervert's guide to the cinema..its an accessible way to get started with him-thats how I did it.
The fear that haunts Zizek's work is that people today are becoming more and more part of the system, unconsciously . The horizon of their presupposed worldview is constrained by what they take to be inevitable truths and desirable fantasies of what will give them enjoyment. Often they do get enjoyment from them, lets be clear. Psychoanalysis shows that people's drives are not fixated on "natural" pre wired objects of desire; instead they are fluid and will motivate people to get enjoyment out of the strangest things (fetishes being the best, and some might say, exquisite, example).
The point is that in the present situation, what with 24/7 social networking; mass media, the pressure to be sexy/beautiful/successful/powerful…to enjoy life…it is less and less easy to challenge the system and there is less and less belief in the ability to change anything or indeed in the need to change anything. In fact the system is taken to be the natural unchangeable order of things, even by people who say they want to change it: they are bought off by free trade maltesers and their conscience is salved.
Then underneath that level you have the steady advance of neuroscience as well as Charlie Darwin's insight that what works reproductively sticks around and what doesn't doesn't, and from there its a short step to "its the genes/deterministic universe that
made me do it; I have no responsibility for my actions and there is nothing I could have done differently".
All this against the backdrop in the West of our christian heritage which before the enlightenment was thought to be the natural order of things, and when belief wanes we search for some other guarantor or guide to tell us how to act.
What Zizek does in his work is to attempt to bring to the surface the motivating factors behind our behaviour (film criticism being one way of doing that) and then salvage space for truly free acts which don't arise out of help from outside the subject, whether that help be belief in God, rules of society, philosophical systems, pre determined universes.