[joseph wilkins]"It's my demo reel, so I want it to be high quality... fairly large, but not clog the viewers bandwidth."
It depends on what you think the bandwidth is of the typical viewer. You have to guesstimate that based on your target market. You could look up by region here but there are other demographic issues to consider depending on the client base you're looking for. http://www.netindex.com/
[joseph wilkins]"I also want to avoid all those Jaggies... I've compressed video in the past and get straight lines that look like they are jagged."
Maybe you're not deinterlacing. Only a guess though.