i Need your advices guys

[eluser]7amza[/eluser]
hey guys
im preparing to code a new big project , so i need your advices guys maybe someone done projects like that ;
so the project is a Uploading & sharing website ..
so the two big problem is :
wich is the best uploading library to use? (with progress bar and multiupload ..)
wich is the best download library to use? (with speed limit for some users and unlimit for premium users like rapidshare) .
thanks.