This phone will get rather hot when you're constantly on the screen and have a few apps running at the same time.
The teamspeak version out now for android will only run on android 2.2 and above,,,,,this phone has that, but teamspeak also needs the ARMv7 processor and your phone only has the ARMv6 processor. If you look on the teampspeak forums in the android section you will see I have requested an update on the rebuild of the teamspeak app for android. They are rebuilding the teamspeak app, but I haven't heard if it will ever support the ARMv6 processor.
Rooting will give you access to everything on your phone. You can delete all sorts of files that are needed if you are not careful though. There are certain apps that need root access to run, so if you come across any of these files you won't be able to run them without root. If you do root your phone, do not go haywire with deleting files and such; only use it to run these certain apps.