I found these two statements in the article to be somewhat at odds with each other.
1. "The viruses that we found are very old, are integrated in the bird genome, and do not have the potential to encode any functional protein product," said Dr Gilbert. "So they do not have any effect in songbirds."
2. "a strikingly slow, long-term mutation rate that is 1,000 times slower than the viral [mutation] rates that had previously been estimated based on comparisons of currently circulating viral sequences only."
If the sequences are being in someway preserved they may well be having an effect. Perhaps not coding a protein themselves but altering the levels, timing or tissue specificity of gene expression in their vicinity. Also the presence of these similar sequences throughout the songbird genome can drive novel DNA recombination events which can result in new phenotypes, driving songbird evolution.

Interesting to look at the HapMap. You should feel very safe if your driver is of sub saharan African descent. They don't seem to have the minor allele at all http://www.ncbi.nlm.nih.gov/projects/SNP/snp_ref.cgi?rs=6265#Diversity . Of course one allele rarely controls the whole show.

and just waste whatever is left over after that

I like the cut of your jib. Furthermore I will happily rent out my North facing roof space (Adelaide, South Australia) to first power company that wants to install solar panels on it. I looked into doing this myself but it is not an economically viable option for an individual household at present and I am too mean spirited just to do it for the dolphins.

Not really, DNA is just a salt by itself it is not really dangerous. Consider if you have eaten anything that was at some point a living object (such as a steak or piece of fruit or a vegetable). That stuff is full of DNA and it hasn't killed you yet. I am surprised that the forensics lab that has been doing this testing did not run the appropriate negative control (cotton swab only) in their PCRs. DNA evidence alone would not lead to a conviction especially if this woman has alibis for the times these crimes were committed (such as she was busy packing cotton swabs at the time of the murder).

The inheritance mechanism is interesting but for practical purposes is not necessary to understand to start applying this knowledge. This holds great promise for those who suffer from neurological disorders where there appears to be both a genetic and environmental component to the phenotype (eg. bipolar). An equivalent "enriched" environment (eg. improved socio-economic conditions, tailored primary education programmes, etc. rather than say institutionalisation) might help families with a history of these disorders reduce the severity of symptoms over successive generations.