This is a wild gess or idea but here goes.
I was woundering if it is possible to connect the
computer to a tv . and if it is possible to connect a
computer to a stereo system.

What i need to know is what kind of cards and or hookups
i need to do these things if they are possible to do.

For stereo hook-up simply remove speakers from line-out,connect a line-in
from stereo.For tv,if you have a cable box theres usually a data connector
to hook computer to instead of monitor,radio shack or similiar have adapters
that do the same.