I've checked your screenshot for the memorex, while it's not excellent, it's still acceptable. PI slightly higher than spec (280) but PO is within limits! I have Maxell DVD+Rs with triple your error rates and they play fine.
I burn all my DVD videos at 8x now and they all play fine. They play fine whether burnt at 2.4, 4 or 8.
I use NERO 6.3, anyDVD, DVD2One, DVDSHrink.
Windows XP Pro / NTFS