If you select the drive in disk management and right-click it, does it give the option to delete the partition or delete striped volume? That should set it back to raw. You definately don't want striped image. Also, I don't think it will allow you to use fat32 on drives of a certain size or larger. I had to use a 3rd party formatter to do this on a drive of mine. I used disk management to create the partiton than used fat32formatter to format the partiton.http://fat32-formatter.softwareandgames.com/
Also, you can't convert between formats without losing data. If you have data on the drive you would have had to back it up first, convert the drive, then restore the data.
To change formats, you need to delete the partition, then recreate it. It will then show up as "unallocated space". Then you can format it. Also, when you create the partition, select MBR, not GPT.