My moms digital camera had the date set incorrectly for years. All of her photos have the incorrect date on them.
How can I change the dates on the photos? Do I need software and does anybody have a recommendation?
Thanks.

I was hoping someone with more photography experience than me would reply, but here is what I can offer.
 
My 3 interpretations of the question:
 
1)  changing a date that is time stamped in the photo itself
   an image editor software like gimp can be used to paste a text box with new date over the existing
   as far as I know you must do this for each photo.
   there are batch photo editors, but have never used one
2)  changing the exif/metadata date
  I have never used one but there are batch editors to change these tags to multiple images files at once.
  I found phatch by a google, never used it or any other though
3)  changing the windows file system date
  another google suggested some software to change these dates from in the file system
   https://superuser.com/questions/71962/how-to-change-file-creation-time-in-the-different-file-systems
 
I am curious which was your end goal and how you finally got this solved.
 
good luck in any case!
 
I hope some others with more photography experience chime in.

Rt click the photo, select "Properties"
 
choose "Detail Tab"
 
Under "Origin" - select and enter new date at right of  "date taken"