Here's what you need...
http://windowsxp.mvps.org/openwithadd.htm
Just for interest...
= got to above link from
http://forums.microsoft.com/TechNet/...9145&SiteID=17
question
= got to this Q by googling: "open with" browse XP problem
site:microsoft.com (about 30th result (3rd page))
I'd actually resolved this before found the page, by using regedit ..
HKEY_CLASSES_ROOT ...