Iv just downloading a 700mb file but im still uploading so fay its uploaded 441Mb, do i have to wait untill its uloaded the full 700mb before i can access the download?
No you dont have to wait before you can open what youve downloaded.
Just click on ‘open directory’ and you can access your downloads. 
Your upload amount will always be a lot lower, because you always download faster then you upload, to help the community along you should try and leave it uploading if people are still getting it to at least the 700mb which you have got.
i dont think the upload amount will always be lower
some people upload faster than they download.
for example, if you have downloaded 10% of a file, the download may have stopped but you can upload that 10% to other people, making your upload more than your download