The following article shows how to create a bootable WinPE disk with Windows Vista Automated Installation Kit (WAIK).
[ExclusionList]
ntfs.log
hiberfil.sys
pagefile.sys
"System Volume Information"
RECYCLER
Windows\CSC
[CompressionExclusionList]
*.mp3
*.zip
*.cab
\WINDOWS\inf\*.pnf
Note that step 2 is not required and is only useful to have imagex tool on the bootable disk.
You may add any other tools or batches to your bootable disk in a similar way.