The simplest way would be to copy the files to a PC, then replace the card in the blackberry with the new one and copy them from the PC to the Card. You can use Mass Storage Mode to easily do this. You enable it as follows:
Status / Options / Media Card
Media Card Support: On
Encryption Mode: your choice
Mass Storage Mode Support: On
Auto Enable Mass Storage Mode When Connected: Prompt
Plug the BlackBerry into a USB port, answer Yes to the prompt, and the BlackBerry Media card will show up as a disk drive in My Computer. Then you can drag and drop.
If you have an SD adapter for the microSD card, then you can put the microSD in the adapter in the PC and make the copy direct from the BlackBerry to the new microSD in one step, without having to use the PC for interim storage.
Put one card into a card reader, connect the phone to the PC.
They will both show as removable drives and you can copy
between the 2 to your hearts content.
If you have no card reader, copy the contents of card A to the
PC. Then remove card A and insert card B. Now copy what
you copied TO the PC to card B.
