Gimp export without ruler

I want to magnify a JPG and save a selected portion as JPG. Magnifying and selecting with the thumbsliders is easy. It seems hard to export what I am looking at. I use "File>Create>Screenshot>Snap", then right click to bring up snap of selected area. Is there a better way? Then I want to save that. There are Gimp frames and two rulers around the image. By selecting "View" I can tediously click away everything except the innermost ruler. It always gets exported. Is there a way to get rid of that?