Ubuntu :: Ati Graphics Drivers Don't Appear To Work?

While trying live usb versions of different gnome and kde distributions, i noticed very unusable performance, however since i read that live media versions of linux did not perform well, i merely assumed that was the reason.

The sad thing is though, i installed ubuntu 10.4 x64 and i am still having the same problems. The only way to get the system slightly usable is to completely disable desktop effects. However, even then, it sort of feels like windows xp before you have installed graphics drivers - like it's not using the hardware at all.

Even the little fish screensaver is basically unrunnable.

My graphics card is an ati radeon x1950 pro AGP version. I read on their site that they only support up to x-org 11.4 and i heard that the linux distributions as of now are beyond that - so i cannot install the official drivers for it (whether they are any good anyway?). I saw in the package manager there are radeonhd drivers also, but i didn't really know what these are and this card is before ati started making their hd series.

So basically, i don't really know what to do or where to turn to in regards to this.

Some other small, unrelated questions are:

How can i increase the amount scrolled with each click of my scroll wheel so it's equivalent to windows? it seems to be one line at the moment, where as in windows i think it is something like 3 - whatever the case, it seems painfully slow.

Also, of my 5 button intellimouse explorer, strangely, the extra forward and back buttons seem to work, but the middle click button doesn't - or at least, holding it in and dragging the mouse to scroll doesn't seem to work - or should it be used for something different in linux?