Just an update, chaps and chapesses - for anyone else with similar problems. Windows XP has the ability to format CF cards if they can be connected as a recognised drive - say e.g. parallel port but not as a PCMCIA. The requirement is to select the FAT option not the FAT 32.
Additionally, I have an RCA Lyra MP3 player and the REAL parallel port software has a recent upgrade which incorporates a CF Format function. This not only formats the card correctly but will also do a Scandisk and 'fix' any problem clusters.
For those with an interest in MP3 and similar, it appears that WMA files are playable on some MP3 players and offer a much improved compression ratio with no detectable loss of sound quality.