With regards to OS3.1, when it comes to using the CD Drive you just need to drag the file out of Storage and dump it into your Devs folder
This is something you should only do if you need the CD drive to transfer a "real" CD file system from another computer.
If it needs to be free, you should go with AmiCDFS2. All other file systems you mentioned are commercial.
CacheCDFS comes with IDEfix but needs registration, otherwise it nags with requesters.
A version of CacheCDFS without nag requesters comes with OS 3.9.
To get AllegroCDFS running, you need a piece of hardware from Elbox which acts as a dongle, for example a FastATA4000 or an EIDE'99.
