u should realy do that as its notalways best quality an if u crash u have to start from the begin
batch render as a traga sequence take to some thing like after effects the export as a qt movie (this way if u crash u just continue to the last frame u were up to)
ps have a look at video mach its free an i think it can convert sequences to qt movies but cheack first if not look on download.com for some other free apps