Parcival I think the thing with book-to-film translations is that filming a book isn't as simple as pointing the camera at the hardcover edition. It has to be reinterpreted for a visual medium, for visual rather than introspective narration, for third-person rather than first-person. Also, it has to fit in a single sitting, unless it's a serialised TV programme, in which case it has to be divided into ~42-minute chunks, which is similarly challenging. So while the book had much, much more detail, and much more in the way of reflection and internal monologues from your namesake, those don't usually translate well to film, and that necessitated a change of perspective. It's a little like radio: My wife always says to me that she likes radio dramas, because the pictures are better. It took me a while to understand this. If you see a visual image, it's someone else's, and is unlikely to have the personal relevance that an image from your own imagination would have. Unless a book is illustrated (and this one was not, of course) the same holds true. It's a two-way street, though: books don't have the soundtrack of a film, and having an actor playing a part rather than your own imagination can add details to the part that you might not have done yourself. You trade one set of benefits for another.
With all those concerns, plus the fact that it's a few years since the book was released, and the world of video games and internet communication have moved on rapidly (so a few updates wouldn't go amiss), the challenges needed to be portrayed differently, or changed altogether. I felt that the way in which those alterations were done respected the original mood and intent of the book - indeed, I believe Ernest Cline (the author) approved most if not all of them - and so in that respect I'd say the film remains true to the book's spirit, while not being a slave to its details. I do agree the challenges in the book were better, but depth is nearly always better in a print medium.
But while I don't share your opinion, it's a perfectly valid point of view, and it's no problem if we don't see it quite the same way.