failing that how does one unistall linux to free up space that is of no use.
First, make sure that the bootloader program defaults to Windows. That way you don't have to mess about with replacing the loader if you don't want to. The easiest way to do that is from within Linux, but it could also be done from the install CDs if necessary, although that's more tricky to get right.
Then you can just repartition the disk, removing the partitions used for Linux and swap, and create a new partition that encompasses all the extra space now on the drive - reformat that new partition with Windows and you'll have your space back, admittedly it will be on a different drive letter, but this is the easiest option.
Many people who want to play with different OSs/versions find that it's handy having all your own data on one partition, and the operating systems on different ones. You do loose a bit of flexibility in terms of large file storage, and this is felt worse on a small disk.
The best way to remove your Linux install and restore Windows to a full size would be to use the qtPartd program from the installer's System Rescue CD (http://www.sysresccd.org/) - that will allow you to delete the Linux partitions and to expand Windows into the free space, leaving everything on one drive letter. This isn't as flexible an approach if you intend to try Linux again in the future, but it will help you squeeze as much space as possible from your disk.
Obviously many people would prefer that you persevered with Linux, but it is important that you can use your computer to work with.
-jim
