My 3500 don't read Verbatim DVD-R 8x TYG02

I burned four Verbatim DVD-R 8x TYG02 with Nero, without errors. But when I try to read this dvd’s, the Explorer don’t recognized most of the times. Only 1 of every 30 attempt is successful and I can read the dvd.
When the explorer don’t recognized the dvd, I run Nero Infotool utility and show the correct info (title, type:dvd-r, …).
But if I use the Disc info option inside Nero Burning Rom program, show this:
DVD session Capacity in use: 1 MB
DVD -RW (!)
Sessions: 1 Book Type DVD -R
(If I run Disc Info the few times the Explorer recognized the Dvd, they show the correct info, Dvd -R type, and the real capacity used).

After this problems I burned one Verbatim DVD+RW 4x MKM02 and is Ok.

My 3500AG is die?
or is only a problem with ths Verbatim’s?

Are you sure they are not fakes?

DVD Identifier:

Unique Disc Identifier : [DVD-R:TYG02]

Disc & Book Type : [DVD-R] - [DVD-R]
Manufacturer Name : [Taiyo Yuden Co. Ltd.]
Manufacturer ID : [TYG02]
Blank Disc Capacity : [2,298,496 Sectors = 4.71 GB (4.38 GiB)]

[ DVD Identifier V4.2.0 - ]

–Nero CD Speed Test results

General Information

Operating System Windows XP
Drive _NEC DVD_RW ND-3500AG
Firmware Version 2.TG
Serial Number 4XI5067S112
Disc Blank DVD
Capacity 4.38 GB

Transfer Rate

Start 6.20x
End 12.42x
Average 10.37x
Type Z-CLV

And, what does that prove for the media?