I've been using a Ubuntu 12.04 off a bootable USB stick so I can have a portable OS. Also, OS variety. I've been using it for a while and I'm still have a few issues. First and most annoying, it often lags/freezes. I'm not sure what word you would use for it, windows will often stop working and go dark/not responding from anywhere between 10 seconds to a full minute and on some occasions, even longer. However, the window eventually starts working again. Similarly, sometimes the whole system will freeze, not just the window. The mouse will still move, but nothing will work. No clicking, no menus, not keyboard shortcuts. Again, it will usually start working. I'm liking Ubuntu a lot, but those issues can make it annoying to use sometimes. For example, it will ALWAYS freeze at some point if I try to watching a Youtube video and I'll have to wait for a minute or so until it starts responding, again.

Aside from the lag/freezing, anytime I download packages, it will always say "package operation failed" when it's done, though it does seem to download/install.

Another issue I'm having is with shutting down. If I open the logout/shutdown menu and click shutdown, it just logs me out and takes me to the login screen. If I try shutting down through the login screen, it won't do anything. As if I didn't even go to it. I've been using the terminal to reboot or shutdown when I need to.

I've looked around for answers for all of these problems and still have yet to find a solution that works. Are these just normal issues with USB booting? I haven't installed Ubuntu to any computers, I've always done USB booting.