Is there a plug-in/upgrade to remedy my dilemma? Sadly no, the last Camera Raw plug-in for CS2 did not include your camera. Obvious really as one came out much later than the other.
Have had a play on the software that comes with the bundled 5D and must say I'm not too impressed - or, am I being hasty? Um, I presume you are referring to DPP? Some people actually like it and prefer DPP's RAW rendering to that of Adobe's Camera Raw. I know what you mean though, one gets used to a certain way of working over a period of time and it's hard to change. You can of course achieve the same effect in ACR as DPP produces straight out of the bag so to speak, but it does take a bit of effort.
Do i need to go to CS4? If you're used to working with Photoshop then in the long term it might be worth while but no, it's not absolutely essential as concerns your current problem. It will of course be cheaper in the longer term to upgrade from CS2 to CS4
before CS5 is released as at this time the reduced cost of upgrades will no longer apply. Normal reduced price upgrades only go back 2 versions.
Any other alternatives out there? Yes, download the free DNG converter (now version 5.5), convert your camera's RAW files to the DNG format, which is Adobe's own RAW format, and these will now open in CS2. Within the standalone converter there is the option of embedding the original RAW files should you not wish to permanently lose your original RAW files but of course this will make the DNG file much larger.
DNG converter available from these pages>
Windows:
http://www.adobe.com/support/downloa...atform=Windows
Mac:
http://www.adobe.com/support/downloa...form=Macintosh