You would need to access AnyRegionChanger and set it to NTSC, if you want to be risky. Don't just do this, though. Do some research to see if it would definitely work or how to recover from it if it doedn't work. Another option would be to get an HD TV or the like. My friend has one, and he installed iPlayer and the view didn't mess up. We were able to view it perfectly.
But as I said, be careful with this process as messing with AnyRegionChanger is just asking for a brick.
EDIT: No, a softmod can't possibly help you with that.