A family of Microsoft word processing software products for creating web, email, and print documents.
Are the documents in question .doc or .docx files? If the latter, you'll undoubtedly get some sort of dialog in Word 2003 warning you that it's a newer file type (assuming you have the Compatibility Pack installed).
In Word 2010, if a document opened in Protected View, you'd see messages such as those shown at http://office.microsoft.com/en-us/word-help/what-is-protected-view-HA010355931.aspx (and, with a change in settings, you can get an Enable Editing button as shown at http://www.thrivenetworks.com/blog/2011/05/25/turn-off-enable-editing-in-microsoft-office-2010/), but apparently Protected View was new in Word 2010, so I'm not sure what would happen in Word 2007.
There's similar information about enabling macros at http://office.microsoft.com/en-us/word-help/enable-or-disable-macros-in-office-files-HA010354316.aspx, but again this applies only to versions later than Word 2007.
The article at http://www.wikihow.com/Enable-Macros-in-Microsoft-Word shows how to change your Macro Security settings so you at least get an opportunity to enable macros. The same settings in Word 2003 are at Tools | Options | Security: Macro Security...