doh!
i just saw your signature. results below

C:\Program Files\Serviio\lib>ffmpeg.exe -i "c:\Documents and Settings\Will\Desktop\Green.avi"
ffmpeg version N-31480-g8bc3a48, Copyright (c) 2000-2011 the FFmpeg developers
built on Jul 14 2011 23:37:53 with gcc 4.4.2
configuration: --enable-static --disable-shared --disable-ffplay --disable-ffserver --enable-memalign-hack --enable-libmp3lame --enable-librtmp --extra-libs='-lrtmp -lpolarssl -lws2_32 -lwinmm' --arch=x86 --enable-runtime-cpudetect --enable-pthreads --target-os=mingw32 --cross-prefix=i686-mingw32- --pkg-config=pkg-config
libavutil 51. 11. 0 / 51. 11. 0
libavcodec 53. 8. 0 / 53. 8. 0
libavformat 53. 6. 0 / 53. 6. 0
libavdevice 53. 2. 0 / 53. 2. 0
libavfilter 2. 25. 0 / 2. 25. 0
libswscale 2. 0. 0 / 2. 0. 0
[mpeg4 @ 01719720] Invalid and inefficient vfw-avi packed B frames detectedInput #0, avi, from 'c:\Documents and Settings\Will\Desktop\Green.avi':
Metadata:
encoder : AVI-Mux GUI 1.17.8.3, Feb 16 201019:42:50
JUNK :
Duration: 01:53:59.95, start: 0.000000, bitrate: 1521 kb/s
Stream #0.0: Video: mpeg4, yuv420p, 640x272 [PAR 1:1 DAR 40:17], 23.98 tbr,23.98 tbn, 23.98 tbc
Stream #0.1: Audio: mp3, 48000 Hz, stereo, s16, 192 kb/s