[capper]

I have 2 laptops with 60GB hardrives in them. In addition, I have 2 extra hard drives that I use for backup purposes. One is 160GB and the other 1000GB. I have been using some software called Synctoy to regularly synchronize my PCs and my extra HDs.
A couple of times now I have had a MAJOR problem in that I have lost a lot of data in certain folders. It simply disappeared. It seemed that both times this happened, I had used the ECHO function on Synctoy.
Since I am starting to accumulate a lot of pictures and music, my 2 PCs 60 GB HDs fill up pretty quickly. So, I would like to store a lot of pictures and music ONLY on my extra HDs and keep the necessary less space consuming stuff on my PCs.
Until recently I had only been using the synchronize function of synctoy and it seemed to have worked very well. Recently, however, I have started using the echo or contribute functions. Frankly, I don't really understand the difference. I can't completely understand the definitions they give of ECHO and CONTRIBUTE.
I want to do the following:
(1) Synchronize the "My Docs" folder between my PCs and extra HDs.
(2) On my PCs, delete all of the major stuff I don't need (like pics and music)
(3) On a regular basis, backup any new data that is added to one of my PCs
(4) Of course, I want to save any new data on my PCs and on the additional HDs. However, I don't want any of the major stuff that I deleted sent back to my PCs.
Which of the functions shoould I be using? What should I avoid doing? Is Synctoy the best program out there or could anyone recommend another?
(A) I am very worried about losing data for a third time.
(B) I need a good consistent program I can regularly backup all of my folders with.
Any suggestions?

[Mike0001]

Probably what's happening is that your pics and music are in My Docs and will need excluding from synchronization. Can't you store them in c:\Media say? Then just copy them to the portable drives. You can then sync My Docs.