A 10.4.7 install is unlikely to work, because it will be a grey installer disk, or a copy of a grey installer disk. It's also probably for an Intel Mac, so you won't get anywhere with that one. Any grey disk is a system specific installer, and won't install on a G4 iBook. The 10.5.4 may have the same issue, unless you know it's a black installer disk. 10.5.6 won't install with that small amount of RAM.
You have a single memory slot. It that slot is empty, you can add up to 1 GB, which will then be fine with 10.5.4 (if that installer will work on your iBook)