If you don't want to use your AC again, you don't have to eliminate anything but the residual freon if you think it's a problem (like if you're not confortable about it leaking slowly).

To have it removed, you'll need to have the freon recovered by a shop with a recovery machine.

One aspect of air conditioning that you'll miss though is having a good defroster because it's a very slow process otherwise (without freon) to dry the dampness.