When you say it's like taking a screenshot, does that mean your cursor stops moving, too?
If you can still move the cursor around while everything else is frozen, then it might be a network/server thing. If EVERYTHING stutters, then it's probably a process on your computer that's using up your CPU. The RO client is pretty picky about how many resources it uses. Make sure you close all background applications and that you've defragged your hard drive recently. It's also getting pretty hot out (at least where I am), so make sure your computer isn't overheating. Some hardware will slow itself down if it start to detect itself overheating.
