Udma is ultra-dma, and dma means direct memory access. Its a way for ide devices to work faster, so to speak.
To check if dma is enabled you can use the command hdparm, in the console, as root. If you
it will list some info about the hda device. If you really wanna see detailed info, use
hdparm -I /dev/hda
To enable dma transfer to hda, for example, do
hdparm -d 1 /dev/hda
But, although checking won't do no harm, if suse is not slow as a whole, just internet, there is little chance its a dma problem. Instead, you should do some research on topics like dns servers from roadrunner, network connection and eth card drivers.