Comment 1 for bug 497984

I had this issue also, the script currently assumes that if you are running on a 64bit host your are able to run 64bit guests with vt-x support. As a temporary work around I modified the select ISO script to present the i386 options if your are running on a 64bit host, this will allow you to download and run i386 images (I have attached it to this bug for now)

I am working on a better solution that will automatically detect if your processor has vt-x support and if it does only provide you with the 64bit options. Hopefully I will get that sorted over the weekend.