How to delete unused apps from a iphone 3G to free up Hard drive space?

How do I delete unused apps from a iphone 3G to free up Hard drive space?

Just hold down on the app and then click the X

Like what Raster said, you have to hold your finger on the app you want to delete. All the apps will start shaking and little X's will appear on the right hand corner of each one. Tap the X on the app you want to say sayonara to, and a notice will come up saying something like this
"Deleting (app) will also delete all of it's data."
Just press Confirm or Delete or whatever the positive one of the two options are and then the lil' unloved app will be gone from your iPhone.

Hold onto any app and there will be a X on the left corner. Tap it and it will be deleted.