Try contig or contig64 from Microsofts sysinternals suite. It defragments all files. Or is that not what you mean with "all my files contiguous"?
By the way, try an SSD in stead of a HDD for the OS disc. There's no need to defrag that. That certainly prevents any errors doing it.
On data disks the effect of fragmentation is very small.
So, the title says it all: while I let my computer defragment two of its hard drives with O&O Defragmenter, it BSODed this error. Thing is, I've never seen it before. Another thing is: O&O definitely touched some system files, as I saw it marking even drivers as corrupt and going on relocating them. So, hoe do I prevent this BSOD from occuring while using this tool or any other tool that can do real defragging, not the joke that Microsoft calls defragging: just sticking fragmented files closer together and calling it a day. I want all my files contiguous and O&O seemed the only tool capable of this.
Any steps I should take to prevent the error? Or should I try and get another tool?