Since i just know Cool Edit 2000 i don't know for sure if it's exactly the same in Cool Edit Pro. But under the menu
Help you can find a tutorial for noise reduction with the built-in features of Cool Edit.
If you want to look at other (maybe even better and more expensive) solutions the
Waves Restauration Bundle seems to give pretty good results. You can access the plugins through the DirectX plugins menu in Cool Edit or any other Wave Editor that supports DirectX plugins.
... and although the
Transferring LPs to CDR: Some Advice deals mainly with noise problems related to LPs you also might find some useful hints about methods of noise reduction on the page.
EDIT: i thought you were asking about noise reduction of tape recordings not the recording itself, sorry. Forget what i've written then. But i really think it's not that important which software you use for recording. Just use the right sample rate, the right resolution and adjust the record level, everything should be fine.