Fuck it... I tried again and got the same result: the disc is unreadable.
this is the log
I 16:30:41 ImgBurn Version 2.5.5.0 started!
I 16:30:41 Microsoft Windows 7 Ultimate x64 Edition (6.1, Build 7601 : Service Pack 1)
I 16:30:41 Total Physical Memory: 4.192.760 KB - Available: 2.937.624 KB
I 16:30:41 Initialising SPTI...
I 16:30:41 Searching for SCSI / ATAPI devices...
I 16:30:41 -> Drive 1 - Info: DTSOFT BDROM 1.05 (H:) (Virtual)
I 16:30:41 -> Drive 2 - Info: Optiarc DVD RW AD-7280S 1.01 (G:) (ATA)
I 16:30:41 Found 1 DVD±RW/RAM and 1 BD-ROM!
I 16:31:30 Operation Started!
I 16:31:30 Source File: D:\Downloads\Halo.Reach.RF.XBOX360-Ungodly\Ungodly-HR.dvd
I 16:31:30 Source File Sectors: 3.827.488 (MODE1/2048)
I 16:31:30 Source File Size: 7.838.695.424 bytes
I 16:31:30 Source File Volume Identifier: DVD_ROM
I 16:31:30 Source File Volume Set Identifier: ec67c000MS UDFBridge
I 16:31:30 Source File Application Identifier: CDIMAGE 2.45 (12/06/2000 TM)
I 16:31:30 Source File Implementation Identifier: Microsoft CDIMAGE UDF
I 16:31:30 Source File File System(s): ISO9660; UDF (1.50)
I 16:31:30 Destination Device: [4:0:0] Optiarc DVD RW AD-7280S 1.01 (G:) (ATA)
I 16:31:30 Destination Media Type: DVD+R DL (Disc ID: MKM-003-00) (Speeds: 4x; 6x; 8x)
I 16:31:30 Destination Media Sectors: 4.173.824
I 16:31:30 Write Mode: DVD
I 16:31:30 Write Type: DAO
I 16:31:30 Write Speed: 2,4x
I 16:31:30 Link Size: Auto
I 16:31:30 Lock Volume: Yes
I 16:31:30 Test Mode: No
I 16:31:30 OPC: No
I 16:31:30 BURN-Proof: Enabled
W 16:31:30 Write Speed Miscompare! - Wanted: 3.324 KB/s (2,4x), Got: 5.540 KB/s (4x)
I 16:31:30 Book Type Setting: DVD-ROM
I 16:31:30 User Specified L0 Data Zone Capacity: 1.913.760
I 16:31:36 Set L0 Data Zone Capacity Succeeded!
I 16:31:36 Filling Buffer... (40 MB)
I 16:31:37 Writing LeadIn...
I 16:31:40 Writing Session 1 of 1... (1 Track, LBA: 0 - 3827487)
I 16:31:40 Writing Track 1 of 1... (MODE1/2048, LBA: 0 - 3827487)
I 16:31:40 Writing Layer 0... (LBA: 0 - 1913759)
I 16:43:45 Writing Layer 1... (LBA: 1913760 - 3827487)
I 16:55:56 Synchronising Cache...
I 16:55:57 Closing Track...
I 16:56:10 Finalising Disc...
I 16:57:08 Exporting Graph Data...
I 16:57:08 Graph Data File: C:\Users\Cristi\AppData\Roaming\ImgBurn\Graph Data Files\Optiarc_DVD_RW_AD-7280S_1.01_14-SEPTEMBRIE-2011_16-31_MKM-003-00_2,4x.ibg
I 16:57:08 Export Successfully Completed!
I 16:57:08 Operation Successfully Completed! - Duration: 00:25:37
I 16:57:08 Average Write Rate: 5.261 KB/s (3.8x) - Maximum Write Rate: 5.599 KB/s (4.0x)
I 16:57:08 Cycling Tray before Verify...
W 16:57:16 Waiting for device to become ready...
I 16:57:27 Device Ready!
I 16:57:27 Operation Started!
I 16:57:27 Source Device: [4:0:0] Optiarc DVD RW AD-7280S 1.01 (G:) (ATA)
I 16:57:27 Source Media Type: DVD+R DL (Book Type: DVD-ROM) (Disc ID: MKM-003-00) (Speeds: 4x; 6x; 8x)
I 16:57:28 Image File: D:\Downloads\Halo.Reach.RF.XBOX360-Ungodly\Ungodly-HR.dvd
I 16:57:28 Image File Sectors: 3.827.488 (MODE1/2048)
I 16:57:28 Image File Size: 7.838.695.424 bytes
I 16:57:28 Image File Volume Identifier: DVD_ROM
I 16:57:28 Image File Volume Set Identifier: ec67c000MS UDFBridge
I 16:57:28 Image File Application Identifier: CDIMAGE 2.45 (12/06/2000 TM)
I 16:57:28 Image File Implementation Identifier: Microsoft CDIMAGE UDF
I 16:57:28 Image File File System(s): ISO9660; UDF (1.50)
I 16:57:28 Read Speed (Data/Audio): MAX / MAX
I 16:57:28 Verifying Session 1 of 1... (1 Track, LBA: 0 - 3827487)
I 16:57:28 Verifying Track 1 of 1... (MODE1/2048, LBA: 0 - 3827487)
I 16:57:28 Verifying Layer 0... (LBA: 0 - 1913759)
I 17:03:11 Verifying Layer 1... (LBA: 1913760 - 3827487)
I 17:08:54 Exporting Graph Data...
I 17:08:54 Graph Data File: C:\Users\Cristi\AppData\Roaming\ImgBurn\Graph Data Files\Optiarc_DVD_RW_AD-7280S_1.01_14-SEPTEMBRIE-2011_16-31_MKM-003-00_2,4x.ibg
I 17:08:54 Export Successfully Completed!
I 17:08:54 Operation Successfully Completed! - Duration: 00:11:25
I 17:08:54 Average Verify Rate: 11.175 KB/s (8.1x) - Maximum Verify Rate: 16.052 KB/s (11.6x)