As AquaDoc pointed out - CS2 will work well too!

I use PSP-X, NikonCapture, Neat Image, and RSE and others. Someday I will have CS2 but so far I have not really needed to spend the big $$$ on it. If you are looking for an affordable application then I vote PSP-X or even Adobe Elements (my wife has this on her computer). There are others too that probably would fit your needs. If you do not want to spend anything then check out GIMP.

Oh yeah a few more that I did previously. Some came out better than others.