Cylinder ridge

You can run it with a ridge, but like Demon said, replacing rings (or removing pistons you need to re-use) and leaving the ridge is asking for issues. The actual "ridge" has aradius as it was worn by the worn rings. Your new rings have a sharp 90° angle and as the fresh ring hits the rounded ridge it twists and can break pistons or itself, in addition to losing ring seal at the most important spot in the piston's travel (TDC). If you have to have the lower end good, I'd suggest you buy a crank kit with bearings and simply replace the crank and leave the rings as is. It's cheaper and safer than trying to make a purse of a sow's ear.