Rose, while the Mac doesn't have that issue (Photoshop, or any other program, doesn't dare throw up a "background,"gray or otherwise, behind an application on this side of the street), I can tell you that most Mac-based professional designers don't have wild desktop colors, patterns, etc.What we see in the "background" IS our desktop, which of course we set as we please.
We have total control of the background, at any time. Guess what most of us have our desktop colors set to? Plain old, non-sexy neutral grey
Your mileage may vary, and I'm not about to tell you how to best work. But a neutral gray doesn't interfere with with you're working on in Photoshop.