It depends:
If you want to keep it as a momento of your grandfather (for sentimental reasons)-- than on the wall it should go. They would look nice on the wall and I'm sure that's why people buy them in the first place (its not usually serious collectors).
Remember that the longer its on the wall the chances of it fading, or deteriorating in condition are higher. The value of these will likely go down in the future. As stated by others here, the BV may be $500 but you'd be lucky to see $300. That's because sheets aren't convenient to collect. The demand for them will always remain iffy.
If you want to start collecting paper money-- I'd put it on eBay ASAP and then put the proceeds into different kinds of notes. If you are already a collector than I'm sure you've got a good idea what you want. If not, then go to the library and take a look at the Charlton guide to Canadian Government paper money (Ed: R J Graham), read up on how to collect, and see which series interest you.
Good luck!