Super slow Macbook

I have the first model of the basic white macbook. 2 years old. 2g RAM upgrade and 500g external drive. Upgraded to leopard 3 months ago. 12g free on internal drive.

Recently my macbook has become incredibly slow. Using mainly safari and mail and itunes. Always going to spinning disk. Even the other day playing music on itunes for a couple of hours and then that got stuck. Don't know what to do. I did a lot of stuff to try and help as listed on this site but it has made no difference. Please help as is becoming impossible to use.

My first guess is the HD is filling up - you mentioned only 12GB left.

Anytime you are under 25% free space they will continue to slow and anything under 10-15% you are asking for trouble.

Clear space by backing up to an external now. Run permission repair and give it back more HD space on the main drive. Anotehr possability is the drive is starting to act up so back up and watch the performance before it bites you.