Just use the new client to send your coins to a new wallet. Leave the dust spam in your old wallet and throw the wallet away and forget that you actually own those coins because they are worthless anyways.
Remote coin kill switch? So 1 person decides about protocol changes, and that I can't use my coins anymore? Seems like some things that people criticized about SC2 are now happening at LTC
But I know, that's a totally different story...