Things to consider when upgrading crankset
The crank you point to would probably fit on your bottom bracket, but might result in a bad chainline.

There are two things to consider when replacing your cranks: the interface between the cranks and the bottom bracket, and the distance from the centerline.

Your old Suntour cranks and the Shimano you link to both use a JIS square taper. So the interface is fine. 

However, your old cranks are designed to be installed on a 122-mm bottom-bracket spindle (and I'll assume that's what you've got), while the Shimano you link to is designed for a 113-mm spindle. You would be going from a triple to a double, which would make up for some of the difference, but I think the Shimano would wind up riding a few mm farther outboard than it's intended.

If you could find replacement chainrings that fit your cranks, that would be an easier and cheaper option, but large chainrings for mountain-bike cranks are apparently impossible to find. And I'm not sure what the BCD measurement is on your Suntour cranks.