I would go ahead and make the video with the full HD settings on your T2i.

Then whatever software that you're going to export it with will most likely allow compression of the file.

I use Aperture 3, iPhoto, or Quicktime....they all allow this.  Check whatever software you will use to view the video.

I'm around for some basic free software now.

The best free software is FFmpeg, if you're not afraid of a command line. Assuming you're on Windows, download and install the FFmpeg "windows binary" which doesn't require you to compile it ;-)

Make sure you know where the 'presets' folder is (it contains a range of configuration files that set parameters to standard profiles automatically), where the FFmpeg program is, where your input file is, and where you want to put your output file.

Then create a batch file according to this pattern:

set FFMPEG_DATADIR=C:\FFmpeg\presets
c:\ffmpeg\ffmpeg -i "E:\LR\2012\2012-01-12\MVI_2802.MOV" -an -vcodec libx264 -vpre slow -vf scale=1280:720 -b 5000k -qmin 35 -qmax 40 -aspect 16:9 -threads 0 -g 25 -f mp4 -r 30 -y "E:\LR\2012\2012-01-12\MVI_2802-shrunk.MP4"

Those parameters shrank my 52Mb video file to 2.6Mb so it's pretty aggressive. Let me know if you try this, but want to tweak the compression.

I'm not sure if I'm on pro or normal quicktime, but its what I use to make files extremely tiny and still have tons of quality.

Download quicktime player,

-Open your file in quicktime
-file
-Export
-Export option
-Play around with the settings.

This will shrink your files down to a fraction of a size.  Its great!