uninstall Ubuntu

David you are about to uninstall ubuntu but you must consider your decision once again .. david linux is the future. There are no crashes as in windows .. no viruses so your data remains safe .. free support from the large community .. as fas as difficulty is concerned you can ask more question as many as you can here or on chat IRQs XCHAT in #ubuntu . There are lot of people there to help you configure anything .. I'm sure you will enjoy this OS .

As far as uninstalling is concerned you should first install windows 7 using bootable cd and then remove Ubuntu partition using Disk management in control panel in windows ... But still consider your decision once more...

You don't really uninstall ubuntu. If its the only OS you have then simply boot to the win7 install cd and tell the win7 installer to delete all the current partitions and use the unallocated space to install windows 7 as you wish.
Ubuntu is not the future but neither is windows. The OS is a tool for a job and if it simply doesn't work for you or doesn't do what you need then I understand you reinstalling windows. Linux is not always the answer despite what fanboys say.

can you tell us why you weren't able to connect to the Internet, we might be able to solve that