All of your Firefox web browser's data, including bookmarks, extensions, extension data such as Greasemonkey scripts, are stored at this location:
C:\Users\<your user name>\AppData\Roaming\Mozilla\Firefox\Profiles\7w22ldgs.default
The name 7w22ldgs.default may not be the same on your computer, but you'll recognize it right away.
Copy the contents of this folder to the corresponding folder on your new computer.
To see how to do the same thing with Google Chrome web browser, consult How Do You Restore all Data of the Google Chrome Web Browser?
If you have any questions let me know and I will do my best to help you!