Is this what you meant by hanging animations?

Hehe just kidding sorry I couldn't resist myself.

As to your problem I saw that on your site but have no idea what the problem could be? Do you know how fast the host machine is? Can you see the CPU usage in like a CPanel or something? Even though it is just a simple scroll code only thing I could think of is the animated gif and the scrolling java are both competing for CPU overhead.

Personally I find scrolling text annoying anyways I would just not use the scrolling text and put some kind of static newsflash type block somewhere to alert your viewers of your important messages. But thats just my opinion, and you know what they say opionions are like