What's the best way to cap a show?

dvd recorder?
tivo?
capture card?

what's the best way to convert them to xvid without flaws like stutter video,
sync problems and darkness?

the easiest way is to avoid any conversion between digital and analogue. if you
get a hdtv capture card, you can record a mpeg2 transport stream, and after you
run that stream through a program like projectx (which fixes the errors), you
end up with a program stream similar to what you would find on a dvd. you then
edit out the adds and convert to xvid using a similar method to converting a dvd
to xvid.

if you don't run the transport stream through projectx or a similar program,
your resultant xvid video might have sync errors. the projectx stage takes a few
minutes, which is why it is sometimes not done on scene releases.

darkness or incorrect colours is a result of using an analogue capture card. if
you use a digital capture card, you will avoid this problem.

does a tivo allow you to transfer it's recordings to your computer? if it does,
then that might be a suitable method.

take a look at http://wxw.doom9.org/ for more information