They stated on the entertainment.com website that if you purchased the printable version of the book, that you could print the coupon for the HoJo right away, so I believe for the printable version you wouldn't use your code, but rather, the printable coupon.
Edited to add: Once you are 'viewing' the Orange County entertainment book on their website, just hit the tab 'see more' (under fine dining, etc.) and then on the left hand side a search box shows up. Type in Howard Johnson and 2 hotels show up.... select the one you want, and then you will see that it states 'Print this coupon today when you buy this book.' It looks like they will still send the book, though, [which is different than the online version that Shakthi, the OP, posted about] and I am assuming they may state on the coupon that the card [that will arrive with the book] must be presented?? Does anyone who already has an entertainment book who is able to print up a coupon know what the coupon would state on it? Thanks!