I wrote this reply yesterday and the database problems meant it got eaten.
The things you can turn off in the Nero dialog DGK30 mentions fall into two categories.
The first category are the buffer underrun prevention technologies. They go by various names - though are often just described by Nero as 'buffer underrun prevention' or similar. There's only a handful of cases in which you may want to turn those off - one example is when you're mastering a disc for duplication, where you'd rather have a buffer underrun than the on-disc artifacts (which these days are very small indeed) of the prevention technology.
The second category could be described as adaptive write strategy technologies. SmartBurn falls into this category - the idea is that the drive monitors the quality of the burn as it goes along, and if it detects that the burn is getting marginal, it will slow down the write operation. If anything, turning these off will increase the speed of the write. However, I suppose it's possible that they may enable some write strategies that are otherwise disabled.
The most likely answer to my way of thinking is that the drive simply doesn't have a 1x burn strategy for the type of DVD media you're using. I know the NEC ND-2500A has no 1x strategies for DVD-R or DVD+R.
This may be the reason why the original poster was given the media. The current crop of 8x DVD writers are really optimised for operation on 4x or faster DVD-R and DVD+R media, and don't always work that well on 2x and slower media.