Here are the results of the re-run after the fix.

aswMBR version 0.9.5.256 Copyright(c) 2011 AVAST Software
Run date: 2011-05-08 11:33:25

11:33:25.550 OS Version: Windows 6.0.6002 Service Pack 2
11:33:25.550 Number of processors: 2 586 0x170A
11:33:25.550 ComputerName: IAN-PC UserName: Ian
11:33:43.318 Initialize success
11:33:47.858 Disk 0 (boot) \Device\Harddisk0\DR0 → \Device\Ide\IdeDeviceP1T0L0-1
11:33:47.858 Disk 0 Vendor: Hitachi_HTS545025B9A300 PB2OC64G Size: 238475MB BusType: 3
11:33:49.902 Disk 0 MBR read successfully
11:33:49.902 Disk 0 MBR scan
11:33:49.902 Disk 0 TDL4@MBR code has been found
11:33:49.902 Disk 0 MBR [TDL4] ROOTKIT
11:33:49.902 Disk 0 scanning C:\Windows\system32\drivers
11:33:58.265 Service scanning
11:33:58.686 Disk 0 fixing MBR …
11:34:08.701 Disk 0 MBR restored successfully
11:34:08.701 Disk 0 Windows 600 MBR fixed successfully
11:34:08.701 Disk 0 trace - called modules:
11:34:08.701 ntkrnlpa.exe CLASSPNP.SYS disk.sys acpi.sys hal.dll ataport.SYS PCIIDEX.SYS msahci.sys
11:34:08.717 1 nt!IofCallDriver → \Device\Harddisk0\DR0[0x855592b8]
11:34:08.732 3 CLASSPNP.SYS[82fa38b3] → nt!IofCallDriver → [0x84eb0918]
11:34:08.748 5 acpi.sys[806926bc] → nt!IofCallDriver → \Device\Ide\IdeDeviceP1T0L0-1[0x8450a8a0]
11:34:08.748 Scan finished successfully