
Welcome Rita!
The problem you're having has nothing to do with proprietary vs freeware computer programs. The lack of support for SVG in Windows, afaiu, refers to the inability of Internet Explorer to display SVG images. It has nothing to do with being able to use SVG or Inkscape in Windows. (Otherwise if Windows did not support SVG at all, we would not be able to use Inkscape in Windows at all, right?) (Btw, Microsoft is now planning to have SVG support in IE, and limited support is expected in IE9. I suppose it's already available in the new IE9Beta, although I'm only guessing.) So no, Windows 7 is not the issue with printing that you're having.
My first thought is that your new copy of Inkscape may have different settings than your old one. Or it may be something in the file. Or there may be a bug in Inkscape? Despite the new computer, you're using the same printer, right? Just to be clear
Since I'm not terribly well-informed about bugs, and I can't think "right off the top of my head" what settings might be involved, let's start with the file. Would you please upload your SVG file as an attachment to your reply? (You'll need to use the full editor - Post Reply - rather than Quick Reply.)