Re: aikido vs jiu-jitsu
when someone has you in the mount theres not much you can do because their just gonna pound you. the best thing to do is try and work a choke and keep them close to you to avoid the strikes. i agree with whoever said take jiu jitsu, because there are ways of working submissions from this position if you know what you are doing. it wouldn't hurt to check out some Gracie BJJ videos as an aside if you don't wanna take up the art properly, the ones i've seen are great and very detailed.