If you are lucky, your dropouts will be somewhat horizontal and it will allow you to eliminate the derailleur all together.

Then, you'll just need a chain tool to remove the extra slack (links) from it..

You can then just slip the chain onto the cog that has the best line and you should be good to go without much hassle and hopefully 100% free.

If you need a basic chain tool, wally_smart has them for $ 4.95

and if you want a new chain they have those for $ 7.99.

=)

Take some pics for us to see what you are up to with that thing !