You've messed up

The pspi.exe file should go in the gimp plugin folder.

On xp use:

C:\Documents and Settings\yourlogin\.gimp26\plugins\

You don't need anything else from there.

Create a new directory wherever you want. Say C:\plugins\

Restart gimp. Under Filters you should see a new entry called photoshop settings (if I recall correctly). In there you need to add a new directory entry and point it to C:\plugins\ (or whatever you used above). the next time gimp starts, pspi will iterate all subdirectories of that one looking for photoshop '8bf' plugins.

Run the eyecandy installer and pick (for example) C:\plugins\ec3\ as the install directory.

Restart gimp and you should have a new eyecandy entry under Filters.
You can use most ps plugins (like the flaming pear plugins or kai's power tools) by installing then into subdirectories of C:\plugins\

Hope that helps.

-Rob A>