Windows 7 - YouTube Upload Question

I'm thinking of uploading some videos to youtube. I was wondering if after I upload
the videos, does the file have to stay on my computer? I want to watch concerts
on youtube without downloading them, or not even keeping the purchased concert
cd or video disc. I don't think there's anything wrong with just watching concert
bootlegs on youtube, without downloading them (there's bootleg concerts on youtube anyway). I never keep anything that I download anyway (because I know it's illegal to keep bootlegs).

Can windows DVD maker, make photo slide shows set to music? If not, what is a
good software that can do this, besides Roxio Creator 2012?

Also, what software can do bpm to fix audience recordings? Roxio Creator can do this, but I don't want to pay $99 for it. What about Stamp ID3 Tag Editor, can it do BPM? Is there any free software to do this?

Once you upload a video you can delete it, unless you need a backup (if your channel or video gets deleted or you or YouTube remove your video. You can use Audacity to edit Music