All your world saves are located in the folder that you listed, .minecraft/saves. Simply save this "saves" folder to a flash drive or compress (by right-clicking the folder and selecting "send to -> compressed (zipped) folder") and upload it to Google Drive if you wanted to use cloud storage. Once your laptop is formatted, just replace the "saves" folder in .minecraft and you should be good to go.
All of the above applies if you HAVEN't defined any Game Directories in your launcher profiles.
If you have you need to save those folders too.
Each one will contain it's own Saves folder plus folders for:
All of the folders are specific to the profile(s) that use that Game Directory.