ext3 back to ext2 in 3 easy steps 

Converting a ext3 partition back to ext2 is an easy task, as shown in the following 3 easy steps. However, it can also be extremely troublesome. The following steps will make conversion hassle free. For the reasons behind it, and cases that may go wrong (and aftermath), read on the following articles.

That's it.

Optionally you can use parted to confirm the partitions are as ext2.

Tong