The "Links" toolbar exists as a folder within a folder called "Favourites" that is located within the profile space for your user. So if your username is "Fred", there will be a folder in C:\Documents and Settings\Fred called "Favourites" (I'll assume that your Windows install is on C:).
My advice would be to copy the entire "Favourites" folder to somewhere safe (say in your "My Documents" folder), that way you have a backup of all your favourites. Once you've installed IE7, you then have two choices:
To restore the "Links" only:
- Open 'My Computer' and navigate to c:\Documents and Settings, then open the folder for the user (e.g. if the user is called "Fred" there will be a folder called Fred).
- Open the folder called "Favourites" and delete the folder called "Links".
- Now go to the copy you made of your favourites and open up that folder.
- Inside you will find a folder called "Links". Copy this into the "Favourites" folder as found in (1) above. This should restore your links (though they may not appear in the order they were before).
To restore all the "Favourites":
- Open 'My Computer' and navigate to c:\Documents and Settings, then open the folder for the user (e.g. if the user is called "Fred" there will be a folder called Fred).
- Delete the folder called "Favourites".
- Now go to where you placed the copy you made of your favourites, select the folder containing the favourites and copy (CTRL+C).
- Return to the user folder in step 1 (C:\Documents and Settings\<user>) and paste (CTRL+V); this should copy the Favourites folder back.
HTH.