Based on my general city experience (not only European cities, they are not so unique) I wouldn't go without a wide angle, at least 17mm for a 1.6x camera... and definately not for a first time and potentially the last visit. (I have had the pleassure to visit Paris several times but still only bring my 17-50 Tamron, if I now bring the DSLR at all with all the hussle at the air ports)
Since you would like to travel light I say just go with the 17-55.
You may miss closeups on e.g. the gargoyles of Notre Dame and such smaller details but we can't have it all, can we? And with the haze most cities has, it is difficult to get a good shot from distance, eg from the Eiffel tower at the Triumphal arch or La Defence... it most likely will be like milk.
For wildlife you would have to use a macro ;-)
Guided tours may not allow for much time to take all the shots you want .. some "kodak moments" may only be a driveby in the bus !!
So to make it light and competent, take your 20D and 17-55 (depending on how much you shoot, batteries and memories card may come handy .. so may also charger, flash, computer and "the-lens-you-didn't-bring" come)
Oh.. don't forget to focus on the different atmosphere without camera... the vine, the foie gras, the confit de canard, the creme brulee .. boy, I got hungry!!!...
I am making my first vist to Paris am looking for advise to help in
packing my bag. It is a week of pleasure travel, where I will be
visiting tourist sites and walking around the city. I want to
balance traveling light with having the right equipment. I would
appreciate any advise. My list of things to take is below. If you
have other suggestions as well, I would appreciate them as well.
Thanks.
Canon 20D
EF-S 10-22
EF-S 17-55
EF 70-200 f/4L IS
EF 50 f/1.4
EF 85 f/1.8
Canon G7
Canon Speedlight 430EX