I was wondering, instead of using my computer for everything like 2.1 rom upgrade. Can i just use astro and terminal emulator to do everything?
Short answer: no.
Certain commands need to be run during steps where you can't get to the terminal emulator.
ADB is easy to install and get going, if you can't get to it just wait until you can.
ADB isn't that much more complicated than the terminal, but the steps requiring it usually mean it could be more painful if you mess something up. At a minimum make sure to install nandroid so you have a really good shot at CYA.
As for 2.1, I'm most likely waiting for the "final" port to work out the bugs.
Boot animations are easy and fairly safe. Simply copy the one you want to use to /data/local/bootanimation.zip, no need to mess with /system and if you mess up it defaults back to /system/media/bootanimation.zip