We managed to get a 228mb file uploaded to NG with no issues. Although that was converted from Flash using NG's Swivel, and I'm guessing it was designed with the correct settings in mind.
I'd also like to give some constructive criticism for your series (though I understand that what's being uploaded now was made over a year ago and you may already be addressing it). Right now the series seems to lack a cohesive visual language. Part of making movies is being able to tell your audience information visually instead of just verbally, and using things like color, lighting, shapes, etc. as motifs can effectively do this.
Good luck with getting the uploads to work and with future episodes!
VicariousE
As a former video producer in the late 20th century, I can empathize with your plight with sub-par equipment. Unfortunately, I'm in a similar predicament. The NG mp4 API has no quality control, so looking at videos such as yours is next to impossible. Could you put a link to your YouTube channel on this page? I'm off to look for it myself - cross-promotionalization is key to exposure :3
Tanadrine-Studios
You can find YouTube Delura videos directly on the Delura website under "Episodes".
I actually have the same problem; I'm on a slow DSL connection so watching video (especially un-optimized) on Newgrounds usually means long download times.