scripting default browser/open location

In Internet Explorer, the syntax to open an URL into a new window is:

Tell application "Internet Explorer" to OpenURL "[url=][/url]" toWindow 0

You may repeat that with all URL’s you need to open.
In Netscape it may be slightly different (consult its dictionary in Script Editor)
Eelco Houwink

I can get the syntax for each browser… In fact it is virtually the same for all browsers (other than omniweb, which is slightly different.). What I can’t determine at this point is how to get the default browser in OS X via AppleScript.
FYI and everyone else’s, this is what I have so far:

set URL1 to "" 
set URL2 to ""
--need a way to get the name and/or file id of the default browser!!!
display dialog "choose browser. 1=IE; 2=OW; 3=Opera; 4=iCab; 5=chimera; 6=netscape" default answer "1" 
set browser to (text returned of the result) as number 
if browser = 1 then
set bc to "MSIE" else if browser = 2 then
set bc to "OWEB" else if browser = 3 then
set bc to "OPRA" else if browser = 4 then
set bc to "iCAB" else if browser = 5 then
--note chimera does not yet support applescript
-- set bc to "çHIM" else if browser = 6 then
set bc to "MOSS" 
end if
tell application "Finder" to set myBrowser to (name of application file id bc) as string
on error
set myBrowser to "Internet Explorer"
end try 
tell application myBrowser
using terms from application "Internet Explorer"
if myBrowser contains "OmniWeb" then
--OmniWeb does not support "toWindow 0" but seems to open new URLs in new windows anyway
OpenURL URL1 toWindow 0
OpenURL URL2 toWindow 0
end if
end using terms from 
end tell