There is nothing to download for the browser except a standard web page.
You can use SpreadsheetConverter for HTML. It is just a plain web page, and it doesn’t get smart until it is shown in a browser.
No, version 3 will not support Win98 and ME. If you need to use Win98, you will have to continue to use version 2. You find version 2 at the bottom of the download page.
Version 4 requires Windows NT, 2000, XP, Vista or later. Also, Windows Server versions are also supported by version 4.
No, version 3 will not support Excel 95 or 97. If you need to use Excel 97, you will have to continue to use version 2.