EOS digital lens questions

I currently use an old Minolta XG-2 and so don't have any investment
in AF lenses that would sway me to go for the Digital Dynax.
That said, I have some expensive specialty lenses that are M42 and
medium format (Pentacon and Kiev) lenses with MD/MC adapters.
Can the digital EOS cameras use these sort of lenses with an
apropriate whatever-to-EOS adapter?
In particular, the Rebel XT looks attractive because of it's
size/weight and high resolution.
Could I use manual (adapted) lenses in apeture priority mode on this
camera?