Greetings Milestonex,
While it is possible to do this, it may not be in your best interests. There are number of pre installed things that have to remain because some core functions are intertwined. Like gtalk, if it gets deleted, then the market doesn't work. The email app may be another one, i'm not sure. Also, if you remove some things, the OTA updates may cease to function on your phone.
I would suggest a few of options, your pick...
1. Go to the sub forum of your phone, and search for the apps that can safely be removed.
Motorola Milestone - Android Forums
2. Download titanium backup, and use the freeze function to stop the apps from running.
3. Get hold of a file explorer with root option, like Root Explorer or the like, and go into the system app folder and rename the offending app..I.E
crapapp.apk to crapapp.bak
This way the app won't run, but is still on your phone just incase you need to have access to it for whatever reason.
I would not start deleting things until you do one of the three.
Also, once your rooted, why bother going back. Just don't do anything else to your phone. Being rooted in itself doesn't harm your phone, its what you do to it once you have root access.
Just my 2 cents.