If you did it with the Guisarme, I would use the [MENTION=94230]anest1s[/MENTION] method.
If you moved 5' and kicked it, I would just let you kick it maybe light load / 3 feet (so if your light load is 90, that's 30') assuming it is a normal weapon and not like a huge-sized great sword.
Attack the dropped weapon seems the right choice. I could work out the distance like this: 5' x Weapon Size x each 5 points by which my attack roll is greater than the weapon AC (10 + Size)
Where the weapon size: 4 if Diminutive (Dagger), 2 if Tiny (Mace), 1 if Small (Scimitar), 1/2 if Medium (Great Axe), 1/4 if Large (Long Spear)