I struggled with this one, I have to admit. Both have their purpose for being in this tournament. Office Space dominates if this was a contest of social slings, and I tip my imaginary hat to it because I own the film but I don't own Saving Private Ryan. I'd much rather put Office Space on in the background than Saving Private Ryan.
But Saving Private Ryan brought a sense of realism to war films like no other. Too often, the limitations of technology made people suffer through grainy battles consisting of overhead crane shots and comical close-ups on an obvious sound stage. With this film, though, particularly the opening sequence, you are literally thrown directly into the battleground. This is perhaps the first time in any war film that gives the audience the sense that they are SURROUNDED by war, as opposed to just watching it on their screen. Office Space did not revolutionize anything in comparison to this.
If you're voting based on character study, Office Space is a better film. If you're voting based on plot structure and film making, Saving Private Ryan takes it. As hard as it is for a writer to deny a vote to someone who introduces very interesting characters in such a mundane environment as an office building, I have to give the nod to Saving Private Ryan.
Saving Private Ryan.