Replying to Adobe premier help

hey guys I need your help, I've got adobe premier and I've made some quality vids, thing is when I export them to like .avi file and play them back it blows, the video runs real slow and choppy. This has happened with other vid edit progs too like video wave and ulead's. I think it might be my shitty processer 400mhz, that might mess it up when it exports it. Videos that I download are fine untill i get them into the programs. ne1 else have this problem? or know how to fix it.