Just to add a bit of info, I have an HP Pavillion with LG GWA 4162b
burner(HP calls it 640b) and version 1.0 of ImgBurn works perfectly.
Version 1.1 though, I started getting the same hang on "syncing
cache" as the OP describes. I tried 1.2 but it wants to format
DVD+RW instead of just writing over it and that hangs. So
I'm sticking with 1.0. If it ain't broke and all that.
It is a strange business because on some discs and burn speeds
(such as ProDisc DVD+R 16x) Nero 6 seems to burn more smoothly
but at 8x Ritek Ridata DVD-R Nero wants to idle when changing from 4x
to 8x and ImgBurn is smoother. Don't know if it's something
about Nero drivers vs. SPTI but I'm just going with what works
better in each situation.
Anyway, with the discs I'm using(Prodisc DVD+R 16x, Ritek Ridata DVD+r
16x and Ritek Ridata DVD-R 8x) I haven't been getting failures at the end
of burns except with ImgBurn 1.1.
AFAIK the settings are left at defaults.