If I were you I would uninstall LW and FW and then restart your computer. Then go to START>Run and type "regedit". There I would search for any left entry of those both programs (i.e. using Limewire (first) and Frostwire (afterwards) as search query). Those entries I would delete.
Then I would go back to START>Search for files and folders and search there for any left over folders of those two programs (including in the hidden folders). Those I would also delete.
Then I would restart the computer and reinstall LW.
Cheers
FOTH