increase swap after RAM upgrade, but no space available on resting partitions

Hi I am not a linux pro! I have 3 partitions, one swap (1G), one for winNT, and the main linux partition. I need to double the swap space (I have 2G RAM now). With yast I cannot resize (increase) the swap since no space is left in the other partitions. The linux main partition cannot be resized with yast as long as it is mounted and I have a bad feeling unmounting it.. what do you recommend? thanks a lot cheers c