Hi mmalves, thanks for the reply - here's a recent log:
I 19:25:51 ImgBurn Version 2.4.0.0 started!
I 19:25:51 Microsoft Windows XP Professional (5.1, Build 2600 : Service Pack 2)
I 19:25:51 Total Physical Memory: 2,070,256 KB - Available: 1,308,912 KB
I 19:25:51 Initialising SPTI...
I 19:25:51 Searching for SCSI / ATAPI devices...
I 19:25:51 Found 3 DVD-ROMs and 2 DVD±RW/RAMs!
I 19:26:08 Operation Started!
I 19:26:08 Building Image Tree...
I 19:26:08 Checking Directory Depth...
I 19:26:08 Calculating Totals...
I 19:26:08 Preparing Image...
I 19:26:10 Using Layer Break LBA: 2028310 -> 2028320 (VTS_03, PGC: 5, Chapter: 1, Cell: 1, Vob/Cell ID: 4/1, Time: 00:00:00, SPLIP: No)
I 19:26:10 Checking Path Length...
I 19:26:10 Contents: 29 Files, 2 Folders
I 19:26:10 Size: 8,193,228,800 bytes
I 19:26:10 Sectors: 4,000,600
I 19:26:10 Image Size: 8,193,900,544 bytes
I 19:26:10 Image Sectors: 4,000,928
I 19:26:10 Operation Successfully Completed! - Duration: 00:00:02
I 19:26:49 Operation Started!
I 19:26:49 Building Image Tree...
I 19:26:50 Checking Directory Depth...
I 19:26:50 Calculating Totals...
I 19:26:50 Preparing Image...
I 19:26:51 Using Layer Break LBA: 2028310 -> 2028320 (VTS_03, PGC: 5, Chapter: 1, Cell: 1, Vob/Cell ID: 4/1, Time: 00:00:00, SPLIP: No)
I 19:26:51 Checking Path Length...
I 19:26:51 Contents: 29 Files, 2 Folders
I 19:26:51 Size: 8,193,228,800 bytes
I 19:26:51 Sectors: 4,000,600
I 19:26:51 Image Size: 8,193,900,544 bytes
I 19:26:51 Image Sectors: 4,000,928
I 19:26:53 Operation Successfully Completed! - Duration: 00:00:03
I 19:26:53 Operation Started!
I 19:26:53 Image Contents: 29 Files, 2 Folders
I 19:26:53 Image Sectors: 4,000,928
I 19:26:53 Image Size: 8,193,900,544 bytes
I 19:26:53 Image Layer Break Position: 2,028,320
I 19:26:53 Image Single Layer Profile: DVD-R/RW (Media Capacity: 2,298,496)
I 19:26:53 Image Double Layer Profile: DVD+R DL (Min L0: 0, Max L0: 2,086,912, Media Capacity: 4,173,824)
I 19:26:53 Image Volume Identifier: DOCTOR_WHO_TIMEFLIGHT
I 19:26:53 Image Volume Set Identifier: 385A9B58003D0C8D
I 19:26:53 Image Application Identifier: IMGBURN V2.4.0.0 - THE ULTIMATE IMAGE BURNER!
I 19:26:53 Image Implementation Identifier: ImgBurn
I 19:26:53 Image File System(s): ISO9660, UDF (1.02)
I 19:26:53 Destination File: F:\DVD ISO's Pending Burn\Doctor Who - Timeflight\DOCTOR_WHO_TIMEFLIGHT.iso
I 19:26:53 Destination Free Space: 140,806,799,360 bytes (137,506,640 KB) (134,283 MB) (131 GB)
I 19:26:53 Destination File System: NTFS
I 19:26:53 File Splitting: Auto
I 19:26:53 Writing Image...
I 19:30:41 Operation Successfully Completed! - Duration: 00:03:48
I 19:30:41 Average Write Rate: 35,095 KB/s (25.3x) - Maximum Write Rate: 48,964 KB/s (35.4x)
I 19:32:13 Operation Started!
I 19:32:13 Source File: F:\DVD ISO's Pending Burn\Doctor Who - Timeflight\DOCTOR_WHO_TIMEFLIGHT.mds
I 19:32:13 Source File Sectors: 4,000,928 (MODE1/2048)
I 19:32:13 Source File Size: 8,193,900,544 bytes
I 19:32:13 Source File Volume Identifier: DOCTOR_WHO_TIMEFLIGHT
I 19:32:13 Source File Volume Set Identifier: 385A9B58003D0C8D
I 19:32:13 Source File Application Identifier: IMGBURN V2.4.0.0 - THE ULTIMATE IMAGE BURNER!
I 19:32:13 Source File Implementation Identifier: ImgBurn
I 19:32:13 Source File File System(s): ISO9660, UDF (1.02)
I 19:32:13 Destination Device: [3:1:0] Optiarc DVD RW AD-7190A 1.05 (X:) (ATA)
I 19:32:13 Destination Media Type: DVD+R DL (Disc ID: MKM-001-00) (Speeds: 2.4x)
I 19:32:13 Destination Media Sectors: 4,173,824
I 19:32:13 Write Mode: DVD
I 19:32:13 Write Type: DAO
I 19:32:13 Write Speed: 4x
I 19:32:13 Link Size: Auto
I 19:32:13 Test Mode: No
I 19:32:13 OPC: Yes
I 19:32:13 BURN-Proof: Enabled
I 19:32:13 Book Type Setting: N/A
I 19:32:39 Optimal L0 Data Zone Capacity: 2,028,320
I 19:32:39 Optimal L0 Data Zone Method: Copied From Original Disc
I 19:32:41 Filling Buffer... (40 MB)
I 19:32:43 Writing LeadIn...
I 19:32:44 Writing Session 1 of 1... (1 Track, LBA: 0 - 4000927)
I 19:32:44 Writing Track 1 of 1... (MODE1/2048, LBA: 0 - 4000927)
I 19:32:44 Writing Layer 0... (LBA: 0 - 2028319)
I 19:53:30 Writing Layer 1... (LBA: 2028320 - 4000927)
I 20:13:42 Synchronising Cache...
I 20:13:46 Closing Track...
I 20:13:48 Finalising Disc...
I 20:15:17 Exporting Graph Data...
I 20:15:17 Graph Data File: C:\Documents and Settings\NCC\Application Data\ImgBurn\IBG Files\Optiarc_DVD_RW_AD-7190A_1.05_TUESDAY-FEBRUARY-26-2008_7-32_PM_MKM-001-00_4x.ibg
I 20:15:17 Export Successfully Completed!
I 20:15:17 Operation Successfully Completed! - Duration: 00:43:04
I 20:15:17 Average Write Rate: 3,255 KB/s (2.4x) - Maximum Write Rate: 3,376 KB/s (2.4x)
I 20:15:17 Cycling Tray before Verify...
W 20:15:24 Waiting for device to become ready...
I 20:15:47 Device Ready!
I 20:15:52 Operation Started!
I 20:15:52 Source Device: [3:1:0] Optiarc DVD RW AD-7190A 1.05 (X:) (ATA)
I 20:15:52 Source Media Type: DVD+R DL (Book Type: DVD-ROM) (Disc ID: MKM-001-00) (Speeds: 2.4x)
I 20:15:52 Image File: F:\DVD ISO's Pending Burn\Doctor Who - Timeflight\DOCTOR_WHO_TIMEFLIGHT.mds
I 20:15:52 Image File Sectors: 4,000,928 (MODE1/2048)
I 20:15:52 Image File Size: 8,193,900,544 bytes
I 20:15:52 Image File Volume Identifier: DOCTOR_WHO_TIMEFLIGHT
I 20:15:52 Image File Volume Set Identifier: 385A9B58003D0C8D
I 20:15:52 Image File Application Identifier: IMGBURN V2.4.0.0 - THE ULTIMATE IMAGE BURNER!
I 20:15:52 Image File Implementation Identifier: ImgBurn
I 20:15:52 Image File File System(s): ISO9660, UDF (1.02)
I 20:15:52 Read Speed (Data/Audio): MAX / MAX
I 20:15:52 Verifying Session 1 of 1... (1 Track, LBA: 0 - 4000927)
I 20:15:52 Verifying Track 1 of 1... (MODE1/2048, LBA: 0 - 4000927)
I 20:15:52 Verifying Layer 0... (LBA: 0 - 2028319)
I 20:24:01 Verifying Layer 1... (LBA: 2028320 - 4000927)
I 20:29:41 Exporting Graph Data...
I 20:29:41 Graph Data File: C:\Documents and Settings\NCC\Application Data\ImgBurn\IBG Files\Optiarc_DVD_RW_AD-7190A_1.05_TUESDAY-FEBRUARY-26-2008_7-32_PM_MKM-001-00_4x.ibg
I 20:29:41 Export Successfully Completed!
I 20:29:41 Operation Successfully Completed! - Duration: 00:13:49
I 20:29:41 Average Verify Rate: 9,652 KB/s (7.0x) - Maximum Verify Rate: 16,478 KB/s (11.9x)
I'm attaching a DVDINFO file too, any help is greatly appreciated ( ! )