The problem is the low volume of the tyres, you have less "suspension travel" when you hit a bump before you bottom out on the rims, so I don't see how narrower rims would help. Like cedywedy said, inflate to as high as possible. For what it's worth, I run Hutchinson Topslick (26" x 1") on one bike and keep them at almost 10 bar. I have only pinch flated twice in three years as a commuter. Pretty harsh ride though, and don't reckon I'd do it if the roads were rougher.
The problem is the low volume of the tyres, you have less "suspension travel" when you hit a bump before you bottom out on the rims, so I don't see how narrower rims would help. Like cedywedy said, inflate to as high as possible. For what it's worth, I run Hutchinson Topslick (26" x 1") on one bike and keep them at almost 10 bar. I have only pinch flated twice in three years as a commuter. Pretty harsh ride though, and don't reckon I'd do it if the roads were rougher.