ZenCart isn't bad, you could definitely use that, however osCommerce is used quite widely as well or there are many more available. Just go for something which would best suit your requirements.
I would totally agree with the above comments as well, if the client provides the images....its his responsibility as to what he provides...but if he has got it from istock...it should be fine.
There was something that i was a little skeptical about. I know it has been and is being talked about a lot, just wanted some views on what according to you a better online marketing technique, is it the e-mail marketing or the social media marketing? What according to you has a higher conversion rate?
I think the suggestions you have received are very appropriate and important. You should definitely look into them and it is also thought that a site with too much flash might not be very successful from an SEO point of view as well. It becomes more effective, its its kept clear and is navigable easily and also about mobile net users, like me, it would be quite difficult.
Good luck.
There are lots of open source templates that could be used effectively, as mentioned by others it would save you a lot of time and energy. But again it would depend on your requirements and the purpose of it, as michelle and bernard would agree. Both have their own advantages and disadvantages, as with everything else on this planet.
Choose wisely. Good luck.