Viewing VRML is what ExpressVR is about. But how to make it fast is up to you. There are many ways to speed up the frame rate of a VRML browser.
Most users won't be able to speed up ExpressVR because the speed depends on the file. There is one thing you can do as a user... Make your window smaller. This speeds up the drawing of the 3D scene.
For those of you creating VRML here are a tips to making your VRML file viewable at high frame rates withing browsers
Not a good way to make the scene faster is by making the VRML file smaller. Doing this in fact is not good because it means that a VRML creator isn't using VRML to their advantage. I've seen a 100k VRML file slow ExpressVR to a crawl and I've seen a 550k VRML file make ExpressRV fly!
To make browsers fly you need to use VRML to your advantage. There are features of VRML that allow this. First, and most important, use LODs. These make the 3D object detail decrease with dinstance. You need to define the lower resolution objects but it allows you to take away, say, the keys on a keyboard when your a mile away. You won't be able to see the keys from that far away. In fact you can probably use a cube at that distance.
Another way is to use the ShapeHints. Most WYSIWYG software VRML world creator applications will do this for you but I'll tell you about it anyway. The ShapeHints allows a VRML browser to not display the back sides of 3D objects. This is a good idea because you don't see the back faces and because -with- the backfaces it will do twice as much drawing. This slows things down.
Lastly, take out detail that is not needed. The more points and faces in a scene the longer it will take to draw the scene.
Happy VRMLing.