Yes, video compression takes a lot of processor horsepower. MPEG2AVI is indeed your best bet if you want a faster encoding engine...the time it takes to learn it will be well spent. Instead of 14 hours, you're looking at only 5 or so. Grab the GUI by DanniDin and, rather than working from the command line, you should have a much easier time.
There is, however, a code-optimized version of FlasKMPEG by PX3. It's
slightly faster than the standard 0.594 release, but MPEG2AVI will still run circles around it.
The absolute best place on the internet to find the software along with detailed guides/walkthroughs is at
Doom9's MPEG Palace.
Best regards,
Floyd