insufficient memory creating AVI

[mona]

Howdy ... downloaded the software yesterday. Need to create title graphics for a HD digital display and tried various effects and backgrounds. Went to create AVI which worked fine first time (HUGE file for 1o seconds - 900+ mb!!!?) anyway it looked "choppy" when viewed - not smooth ... used defaults in output ... (high quality) ... next time I tried to create an AVI I received "insufficient memory" and have had that problem ever since ... I have defragged, cleaned up temporary files and seem to have way more than enough resources than what they say is needed to run the program ... can anybody help me? system info attached to my profile ... also - do you think this is the right program for HD monitor display - any advice on other potential software that would work for creating graphic/text ads for display advertising in storefronts?

I have the dimensions set at the HD size - 1920x1080 - should I divide that and do it in a smaller area? If yes what happens then when it is displayed at full size on the monitor - would I not lose big time res? does that matter with text objects or would they look just fine ...