What MacBook model is this? Look in >About this Mac>More info>Model Identifier.
Sounds like you may have just upgraded the OS from Snow Leopard or lower to Lion or Mountain Lion, where PPC apps (Power PC processor, as opposed to the "newer" Intel processor in Macs)--Office 2004 is one--are no longer suported in PPC emulation with Rosetta. If that isn't the case and you haven't upgraded, then Office 2004 should still be working.
Although Apple to my knowledge never publicly announced the discontinuation of Rosetta, not at least in its advertising for Lion or Ml, it has been widely known for several years that they dropped Rosetta.
It seems that Apple no longer felt that the licence for Rosetta (it wasn't their own software) was worth it, especially as it would have limited the development of Lion the way they wanted it to be. For this reason alone, I stay with Snow Leopard - I don't like the iPhonification of Macs to be honest.
However, all is not lost! If your laptop came with Snow Leopard originally, you can reinstall it, though it is not quite so simple as simply installing from the original disks - first you have to completely erase the hard drive as Lion uses 2 partitions, and re-partition using the single partition option. After that, Snow Leopard will install from the disks. Needless to say, you should do a complete backup first, or make sure you have Time Machine up to date.
Then Office will function normally. I'm still using Office 2001, though I also have iWork 09 which is superior in many ways.
Let me see if I can make a few educated guesses and save you some time:
You had Office 2004 running on your MacBook but recently upgraded to Lion (or Mountain Lion). When you attempt to run any component of Office 2004, you get a Dialog Box that PowerPC applications are no longer supported.
Your best and easiest solution (although maybe not the cheapest) is to upgrade to Office 2011 and everything should work fine again!
Two factual corrections:
1. Apple extensively publicized the fact that Lion would no longer include Rosetta. The problem is that the everyday normal PowerPC app Mac user had no idea what Rosetta was, that they were using it nor what its absence in Lion would mean for their everyday life!
2. Apple's license to use the underlying technology of Rosetta expired with the release of Lion (and now Mt. Lion). The third party company that licensed this technology to Apple back in 2005/2006, was acquired by IBM, who still champions the PowerPC platform.
It is doubtful that IBM would have re-licensed this technology to Apple at any reasonable price... Apple's "feelings" had nothing to do with it.