Acer 8104 Audio input/output Multiquesitons

Greetings,
I have an Acer 8104 with the audio output (headphones), and input (microphones) 1/8 inch jacks in the front. The following questions pertain to this as well as the bluetooth device:

1) The input jack/multi purpose jack doesn't seem to work when I hook a microphone up. How do I get it to work? (yes it is unmuted)

2) The external microphone located on the laptop causes the computer to make a horrible screaching sound if unmuted/activated (I almost bashed my computer...serious, like babies in a blender). This happens even if the headphones are plugged in which would eliminate the possibility of feedback.

3) The next problem is one of my own doing. The headphones worked fine as long as the external microphone wasn't on, but I accidently tripped over the headphone wire and buggered the outlet. Any ideas on how to replace/fix it. I am betting its attached directly to the motherboard and i am SOL. In the mean time my warranty expired 4 days ago (not that this was covered), and ACER support refuses to respond to me via email (anyone know a number where i can talk to a person?

4) If nothing else works I was debating on getting a bluetooth headset. Anyone know if the the bluetooth works with stereo headsets (A2DP compatible)?

Thanks for the help, and I look forward to anything anyone can throw my way.