example:
if u want to play WMV/AVI/MPG/Mp4 etc files with VLC
Right click on a associated WMV/AVI/MPG/Mp4 file.
click>open with
click>choose Default program
Select VLC player enlisted from there or browse for i
Check "Always use this selected program to open this file"
Click okey.

here u are, all .wmv file will open with vlc.
for streaming TV? do u think vlc supports this? if not then u will fail.
but i got another solution for u
check this link :
How to stream live tv or video with VLC/videolan