It depends on what is on those pages.
For example, if you have 1000 pages of text/html modules, you can export the portal as a portal template and use that to create a new portal in your new install. So long as you tick "Include Content" when exporting, it will bring the info across.
Only some modules actually work like that, but you can always just test it out and see what happens. Your detination system should have all the same modules installed beforehand. Roles and permissions and placement of all modules will come across, but user accounts will not. You can use a third party module to transfer those.
You'd need to also check profile properties and folder permissions to ensure you have the same setup after the transfer as you did on the old system.
With some care anf effort it can be done.
If however you have a thousand pages full of modules that can't export content then you're in trouble and will either need a db export or a lot of manual effort.
It'd be good to report your results back here too.
Rob