72 dpi is fine for upclose viewing unless you are using very small text, which I doubt you are doing on such a large area. But you cannot enlarge it once you import it into the actual size document. So as per my previous post, if you make the document those dimensions, when you import the layer, do you just stretch it larger or you will lose quality. That is why I was saying you will need to duplicate it more than 2 times if you intend to cover the entire wall with the same image.
Terms defined:
LPI = Lines per inch = Linescreens used for offset printing
DPI = dots per inch = printer capability
PPI = Pixels per inch = raster image data
I have found that 100 ppi "can" work pretty well without seeing the rasters if it is a large image. 250ppi seems to be a sweet spot of file size versus quality. Particular images may show "jaggies" - images that have a lot of diagonal parallel lines are ones that come to mind - and may need higher resolutions.
[LPI setting could help - but I think that is archaic/artistic at this point]
All these ppi numbers are actual size. Sometimes it is easier to scale down in the file and scale up when outputing.
If your image does not meet the quality requirements - you can up the resolution - but this will often require a Gaussian blur to hide that you did it. I'd suggest printing a swatch of the image to see.
If there is text on the image - that needs to be set in Illustrator or InDesign to make sure vectors are used.
Your current file is 37ppi at the height constraint. I'd say that is too low. Resample the image in photoshop to 100ppi - Gaussian blur it (perhaps a bit or unsharp mask) and print a small area to check. Pick an area that might show problems.
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