What to do with my RAW (NEF) files...

[wgdbradley]

Once I have taken them and they are on my PC, what software can I use to edit them, and what benefits are there of these file types over JPGs?

[wgdbradley]

And I have PSP9, not sure if thats good enough or do I need to download some kind of plugin?

[PaulBoy]

Once I have taken them and they are on my PC, what software can I use to edit them, and what benefits are there of these file types over JPGs?

I assume if they are .nef files you are a Nikon user? I suggest you download the 30 day trial of Nikon Capture NX which is their editing software & you will not require any further programs / plugins etc to view & edit your pics
As to the benefits well the RAW it is well documented but basically it is the image you took without any form of compression & Capture NX will allow you to adjust vitrually every aspect of the RAW image like exposure sharpness etc
If you decide to buy Capture NX I suggest you PM Kerso here as he sells it as cheap as anyone (@ £80-£90 IIRC)
Paul ;)

[awp]

Even better - download Nikon ViewNX - just released and FREE - allows viewing and some basic editing of Nef files - maybe all you need to get started. HUGE advantages shooting RAW over jpeg - put simply - everything is adjustable afterwards - WB - Exp comp - etc as these valies are 'tagged' to the file and not set in stone as they are with jpeg - so you have a lot more choices you can make at the edit stage. Downside is bigger file sizes and maybe slower to shoot/write to the card in the camera - depends on the camera you have.