I don't have any experience with printers that offer borderless printing, but the thing they have to get around is the gripper margin. In offset printing, the gripper pulls the paper through the press, so you can't have image that goes all the way to the edge of the page on the lead edge. That's why people who need borderless printing on press will use a larger page with crops, and bleed the image into the crop area, so that the cutter can cut through bleed, and if the trim is off by a bit, it will still look like it was printed to the edge.
I know that office printers also have the gripper margin limitation, so I'm not exactly sure how borderless printing is accomplished. Maybe the lead edge is pushed through and grabbed after it's imaged, but that's just a guess. From what I can see in your second image, it looks like the image was placed further down the page than you had intended, which is another limitation to office printers—the fact that there is some amount of drift between where the image is supposed to print and where it actually does. If you pick something on the page and measure from the top edge to it, does it measure the same as it does in InDesign? If it's also a bit lower, then I think you are dealing with the image drifting a bit. If the top is where it should be, I'd double-check that the paper size and the document size aren't off by a bit.
I don't own a borderless printer, but I've heard that they accomplish borderless sizes by scaling the image. You might want to use a ruler to check the sizes of things on the print and see if they've been scaled up.
Peter is correct (no surprise there). Borderless inkject printers scale the page up to print to the edge of the page. These printer are not intended for precise page layout. They are for printing photos where cutting off a few pixels off the edge is no big deal.