Forget about the 18-200, it compromises everything for zoom range. Instead of getting two separate lenses for the 20 mm and the 35 mm, why not go with a 17-40 mm f4 lens, or a 24-70 mm f2.8? I wouldn't recommend the 18-55 kitlens either, the 24-70 mm has enough range to act as your walk-around lens and the 70-300 would match up great in zoom range. So basically, by getting a 24-70 mm, you save cash on a crappy 18-55 mm, an moderately priced 20 mm and a moderately priced 35 mm.
I've got a 40D with a 17-85 mm kit lens which is ok, but has some severe barrel distortion at wide angle. I'm currently saving up for a 70-200 mm f2.8 IS and after that a 10-22 mm. After that I might get the 24-70 and get rid of the 17-85.
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The digital picture