I am now on Office 2011, can I delete folders from Office X and 2004?

I have had MS Office for Mac for a LONG time.  I need to clear out some space on my hard drive and found big chunks of data in a folder called Microsoft User Data.  There are several folders in there that I would like to delete if it will not affect my current MS Office.
these folders are: Office 2008 Identities, Office 2004 Identities, Office X Identities.  There are a few other folders but their size is inconsequential.
What can I delete to free up some space?

also, where can I comment on potential changes to Office for future updates?

thanks,
Toby Scott