Your problems are not related to the Zen-Cart.com server problem that happened earlier today. There could be no correlation.
First, the center image on your home page is 1.5 MB in size ... that's absolutely ludicrous for a website. Anyone on a slow connection will have to wait 5 min for it to load ... and most would leave before it did.
Second, what version of Zen Cart are you using?
What addons do you have installed?
Third, look at the bottom of this page, under "Similar Threads" for tips on optimizing images, dealing with fuzzy images, etc.
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