How can I retriev messages from my home ohine/ansering machine???? PLEASE help. Model # 29893GE1B

Please read this manual for your model on Panasonic's site and go to the Answering System - Remote Operation section, there's a part that deals with retrieving messages by calling your number:

http://service.us.panasonic.com/OPERMANPDF/KXTG6431-MUL.PDF

Ms. - I'm so sorry for your loss.
The least difficult and technical way to retrieve the messages to save would be to buy a digital voice recorder as shown here on Amazon.com
Click Here
or any larger store that sells consumer electronics. There's no need for expensive as spending more money would not get you any better quality recordings of your son's messages. The only feature you require is that the device have a USB connection so you could connect it to your PC and save the recordings to your PC hard drive.
Before you start recording messages be aware that because the messages are digital you can replay them as many times as you need to to get the right quality withou causing them any damage.
To start saving the messages you would place the microphone of the digital recorder over the phones speaker on the left side of the phone at about a distance of 4 to 6" to start. The manual for the digital recorder probably would give you specific advice about this.
The recorder works like a minauture tape recorder. To start recording messages press the RECORD button on the digital recorder, a few seconds later hit the phones PLAY/STOP button to begin the message. When the message is finished hit the phones PLAY/STOP button and then the stop button on the recorder. You've recorded the first message. It's a good idea to rewind the recorded message and play it to make sure the quality is adequate (it should not be much different from the original in quality) If it's OK, move on, recording the messages one by one until you are finished.
To save the messages permanently you would plug the recorder into a USB port on your computer and copy the files to the hard drive. As a precaution, please copy the files over to another medium also, either burning them to a CD or DVD or copying them to a USB thumb drive.
I hope this has been helpful. I hope your healing has begun.
Peace, Mikeywaf

Depending on your answering machine, you can call into your house and when it says to leave a message you would enter in a 4 digit pass code to retrieve any messages, etc. But that all depends on your make and model.

The 27831 isn't an answering machine. Please refer to the documentation for the answering machine you have on your phone line. If you require further assistance, please add a comment to this question and specify the make and model of your answering machine.

Here's the manual:
29869GE2 Digital Answering Machine
You will need to set a security code. When you're away you can call your home phone and enter the code to retrieve your messages. Hope this helps.

Call your phone wait till message is over hit #1234 or #9999 see if that works

Since you neglected to specify the model of your Uniden DECT 6.0 system I can only suggest you select it from the list beginning here to download a copy of the manual.

When you first installed your GE Digital Messaging System, you heard the code that was auto set for it. Once you are out and away from home, phone home and during the answering machine promp press # and then the promps will ask you for your 'pass word [code]. Please be careful as messages deleted by you, you may not beable to retrieve them. This machine doesn't run by cassette tapes.
~ hope the above helps.

unplug NOW before someone tapes a messages over the "deleated"one try plugging back to power after machine has had 5min downtime this may 'reset' so you can retrieve if this does not work call manufactor they may know a trick but do not reconnect because if someone tapes over its gone!

GE26993 user guide available at http://phone.manualsonline.com/manuals/mfg/ge_appliances/26993_26994.html