Newbie question about what video profile to use

Hello, I am new to kdenlive (new to video editing in general!) and wanted to use kdenlive to make a video that contains footage shot from a webcam and desktop capture. I am using ffmpeg to screen capture my desktop, and here is what ffmpeg tells me about the video format:

FFmpeg version SVN-r19134, Copyright (c) 2000-2009 Fabrice Bellard, et al.
configuration: --enable-gpl --enable-nonfree --enable-pthreads --enable-libfaac --enable-libfaad --enable-libmp3lame --enable-libtheora --enable-libx264 --enable-libxvid --enable-x11grab
libavutil 50. 3. 0 / 50. 3. 0
libavcodec 52.30. 2 / 52.30. 2
libavformat 52.34. 0 / 52.34. 0
libavdevice 52. 2. 0 / 52. 2. 0
libswscale 0. 7. 1 / 0. 7. 1
built on Jun 8 2009 12:12:42, gcc: 4.3.3

Seems stream 1 codec frame rate differs from container frame rate: 1000.00 (1000/1) -> 62.50 (125/2)
Input #0, asf, from 'video40.wmv':
Duration: 00:00:08.96, start: 3.000000, bitrate: 3923 kb/s
Stream #0.0(eng): Audio: wmav2, 32000 Hz, mono, s16, 20 kb/s
Stream #0.1(eng): Video: wmv2, yuv420p, 960x720, 2922 kb/s, 62.50 tbr, 1k tbn, 1k tbc
At least one output file must be specified

The desktop screen capture is in 1920x1200, but I would like the final output to be the best to display the webcam video. Would a widescreen format be possible?

Can someone please help me understand how to begin, particularly with what video profile to choose? I have no idea about that. Thanks!

Create a custom project setting using a resolution of 960x720, whatever frame rate you want, pixel aspect ratio of 1/1 and display aspect of 96/72 (or 12/9).