Try backup  and restore  option in sharepoint  designer

The best way to restore  sites in sharepoint  is to restore them via
command line using stsadm.exe. Go to a command prompt and run
stsadm.exe from c:\program files\common files\microsoft shared\web
server extensions\12\bin and type stsadm.exe -o backup  and press
enter. You will see the command line switches to use.

Detailed info is avaliable from MS-

www.microsoft.com/.../c2861881x.mspx

Thanks for the best option given..but my doubt is when i take a back up in one
machine containing one localhost/ip in the url ..and now try to restor it in
another machine  containing another domain/localhost /ip will my url change and
by what url name is my restored site  save / created...
Do i need to recreate the site after restoring  with the backup  information?

Make sure that the both environments are identical in terms of version
and service-packs.

You can also backup  / restore  using Central Admin. I prefer Central
Admin over STSADM because restore options are supplied in a web-form
instead of having to enter in command-line mode. Remember to put
MySites under different port to MOSS site  otherwise you'll get errors
if you're using this method.

To make it even easier you can change the URL of the site and SQL
Server by editing the backup.xml file in the backup folder before
restore.

Forgot to mention: You do not have to edit the XML file but it makes it
easier because you can search / replace old server  names with new ones
and repeat several times. I'm not sure if this is the recommended
approach but I find it easier.

I'm assumming you are doing this using MOSS 2007.

Atlast i sucessfully retored my site  to another using the command-line
technique.Thanx for the reply..I'm currently using SPS 2003 not 2007.
But i one experince problem  ..the dynamic webpart i developed are not
restored to another machine..i agian need to copy the required dll's and dwp
files to another machine..
Can i find any way to solve this or i have to obey the preocess?

You cannot restore  WebParts. Most of SPS content is held in databases
but not WebParts and related resources / files. The recomended
technique is to backup  the SharePoint folder (known as '12' hive in
MOSS) also so that one can restore everything correctly.

If the WebParts are developed correctly then installing  them should
not be a problem.

Also back up web.config files because some WebParts require config
info stored in them (you might require those config values).

Sometimes WebParts deploy DLL files into C:\Windows\assembly (also
called the GAC) and therefore it's always a good idea to install them
instead of backup  / restore.