what IS the point because I am kind of a still looking for it....
are you concerned that somehow your activities on the computer are going to be monitored through your television? is THAT it because I just read your post three times and that's the closest I believe I have got.
lets forget for a moment that this is HIGHLY improbably in the way you seem to describe, but in the event of this, I don't think you are very interesting to anyone unless you are like a government operative / CIA person / terrorist, etc.. No one really cares about your private e-mails to your g/f, your web page about your cats or what books you bought on amazon. Well, maybe Amazon care about the last one but you get the picture. Unless you are living a VERY unusual life, no one really cares and will not bother to spy on you.
web sites and various other forms of "spyware" are another issue, and we have discussed these numerous times on this site. however, the spying in this case is mainly on your activities as a consumer, so that someone can try to sell you more stuff.
your only threat of being "hacked into" if you like is mainly from people who want to use your HDD space and internet connection to host warez sites on. Certainly no one is interested in your personal life.
my advice is not to worry about it, and go get yourself the best graphics card that you can afford. whether you want it to be able to play games on a big TV, or watch TV in a window or both is pretty harmless in my book. Any even if there is the possibility of what you describe, I SINCERELY doubt that you are interesting or important enough to spy on.