When I applied for my current job over the summer, I listed the jobs and professional activities that we relevant. There were definitely some time gaps, but they were due in part to being a SAHM and in part to finding work that simply wasn't relevant. I wanted them to focus on the experience I had that was relevant.
Both my cover letter and my resume focused on what I had done that made me qualified for this job. Maybe I'm weird, but I had more than enough previous jobs, professional experiences, volunteer coordinator activities, etc, to choose from and could easily fill more than one page.
I don't think you need to mention it at all unless you think it's a selling point. I think most employers would just assume you had other jobs during those time gaps, but that those jobs weren't related to the current job. If they want to know, they'll ask. You can think about whether you want to say you were a SAHM or you want to tell them about your husband's business. Whatever you do, sell it!!!
Just my 2 cents. Good luck!!!