I own an HTC Chacha and I partitioned my SD card for phone rooting and discorved my phone is s-on so it cant be rooted! So how can I unpartition my SD card to reuse the partitioned space (this partitioned space cant be read by my phone)
The easiest way is to backup the contents of the SD Card to your PC, then delete all partitions, create a single Fat32 partition, and then restore the card contents.
Simply either use the same partitioning tool you did when you partitioned the card to begin with, or one of many free partitioning tools available. I highly recommend GParted.