If you don't have any SLR lens to start with, and won't go into a very large scale DSLR system, I suggest you Nikon instead of Canon.
I am a Canon man, 3 bodies and 10 lens, so I can't change to Nikon.
But when compare 350D vs D70/D70s, obviously D70 is a better camera body, very accurate AF and exposure, good quality build, and all the function you need for an entry level DSLR.
Canon 350D has higher resolution, that is their biggest and only advantage. Canon offer high speed AF, but not accurate
, Canon also have not provided all the function like D70 as they need to protect their 20D market, make sure there is a significant different between 350D and 20D.
The kit lens of Nikon is very good, worth the extra cost. The kit lens of Canon is cheap, but low quality. A lot of my friends end up putting this lens aside and never used it seriously.