Depends on what you consider better. F1 2002 is generally considered to
have the better driving physics, but many people have been very disappointed
with the inaccurate and bumpy tracks. GP 4 is usually reckoned to have
better tracks. So it is a question of which is more important to you,
accurate physics or accurate tracks. Unfortunately you can't get both in
one box. I would agree with the other posters though that F1 Challenge is
your best bet if you can find it, not just for the physics or the mods but
also because there are a lot of excellent community made tracks that you can
download, including 2003 season updates of the F1 tracks that have some of
the problems fixed.