I'd get the 20D with either the 17-85 as a kit (saves $100 or so) or the Sigma 18-125. I'd also get the 50mm f1.8 for low-light work as it's cheap, small & light (130g!).
And I'd stop there. When you get back you'll have a much better idea of what else you might like to get and I really don't think you'll miss terribly much with either of those two lenses that you can't get by zooming a bit with your feet.
After all this is your wedding anniversary trip not a photographic expedition. A bag full of new camera equipment is a lot less spouse-friendly than a new camera with 1 lens on it. Also less hassle to carry and leaves more space in your luggage allowance for souvenirs. :-)