virus software wont load, system sticks

I have tried to load my Norton anti virus software and it
will not load. It starts to load and then just
disappears! I have uninstalled it and have tried many
times to reload it, but like I said it disappears. My
other problem, which I'm not sure is the cause of my
first problem, is everytime I play my games online and
press the forward button and release it, the screen my
characters for example, keeps right on going. As if it is
sticking. Any help with these two problems would be
greatly appreciated. Thanks
Joseph