Dual-booting without NeoGrub/HnS does not delete Windows XP system recovery points, therefore it does not present any danger to your Windows XP installation.
The only problem is that it delete's Windows Vista's recovery points.
Personally, I won't be providing any support for the old NeoGrub method; the existing threads have (pages and pages) of answers that should point you in the right direction - together with Andre's great guide above, that should be enough. There aren't any "tricks" to it or anything, it's simply a matter of knowing which partitions to hide - unfortunately it's a real pain for me to have to figure that out all these tubes away.