Hi minibass,
first of all: WELCOME TO THE DISCUSSIONS!
When you upgrade to 10.4 your applications and documents remain untouched unless you selected to do an Erase&Install. Both options, Simple Upgrade and Archive&Install will NOT move or delete any applications or files from your home directory. In case you did select Erase&Install you will have to reinstall your apps and restore your documents from your backup. The chance to recover any of them is close to zero since the new system was written over your old data.
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