If you just want to insert a bit of text as an embedded Word document (and a
simple textbox isn't good enough), copy the text in Word, then in Excel, on
the Edit menu choose Paste Special, and choose "As Microsoft Word Document
Object". The content looks like it's in a textbox, but when you double click
on it, Word is activated to do the editing.
To insert an entire Word document, go to the Insert menu, choose Object...,
click on the Create from File tab, and browse to select the Word document.
- Jon