Thanks Rugmankc! Your help is very important to me!
I'll root my nexus one tonight!
I'll use the Simple SDK setup and manual root guide (by danger-rat) and the wiki Nexus One/Guides & Tutorials.
[Guide] The 100% Fool Proof Guide: STOCK N1 to ROOT to SENSE UI/CM (Android 2.1)! - xda-developers
Nexus One/Guides & Tutorials - XDA-Developers