Office 2007 features Microsoft Office Document Imaging which, while it is not the best OCR software in the world, will at least be able to get back the majority of your documents.
If it is not installed then you may need to reconfigure your office setup to add it in.
On my system the tool is Found at Start -> Microsoft Office -> Microsoft Office Tools
, as show here:
To scan in a document go to File -> Scan New Document
and follow the prompts to get a series of pages which will automatically be OCR'ed
At this point you will have two choices, you can save the files as .mdi (Microsoft Document Image) format which will keep both the image and text as it's a bit like Microsofts answer to the PDF format, or you can send the OCR'ed text to Word. If you just want the documents for future reference I'd be tempted to save as mdi, if I needed to edit the file then Word is the way to go.
To send the text to Word, go to the menu Tools -> Send Text To Word
which will open an new Word document with the text inserted. I just tried it with a document I had lying about and it's about 90% there, the formatting is messed up (no whitespace) and there are a couple of spelling mistakes but the gist of the document is there.