I don't think it is a matter of right or wrong. Stephen in a parallel post first pointed out that Safari had a built-in facility for picking up the colour profile of an image; Duncan starting this thread added that Firefox 3 with addon 6891 does likewise.

If you care to download one of these and use it for viewing this or similar galleries, you will get the picture with 100% of the colour that the poster intended.

For your own pics, not sure what 'spot' is, but the rest can all be done within NX and you only end up with (a) the NEF file as edited (b) a web version .jpg, say 1024 max width and/or 768 max ht and use the quality percentage in edit>size/resolution to keep file size below 300kb.

If spot is de-spot, ie remove odd blemish, that can usually also be done using NX1.3 appropriate brush selection and pipetting adjacent colour (sometimes with linked enhancement adding some grain or noise to blend). In NX 2 there is a 'healing brush' tool and more keyboard short-cuts.