changing file extension

I saw someone else's previous post similar to mine, and I saw the suggestion for paint.net so I tried that but now my problem is different. If I design a web banner on inkscape and save as bitmap and then open in paint.net and save as any other ext. it adds the white back ground that I can't get rid of. The white back ground don't look so good on a website that doesn't have a white back ground. Any suggestions on how to make it quit adding the white background behind my banner?

First you export to bitmap from inkscape, which makes png file. Png supports transparency.
If you cannot use the transparency you have either add in inkscape a big rectangle of background color to the very below, or in paint.net or gimp add a layer of background color behind the picture before saving to nontransparent format.

Yeah I will have to make do with that I guess. Just no good when you have a website with a background that has effects.

Gif supports transparency, but not as well as PNG does, why can't you use the PNG directly?

Other alternative (but please don't) is to put it in a Flash container and serve it that way.

I am trying to save a file to jpeg or dst file type, how would I do this using inkscape?

Thanks