I want to create a new partition.. help?

Well if you thinking of installing of Windows Vista better to do a compatibility check online. If you have done that the second major issue is the capacity of your hardisk. I m running Windows Vista Ultimate and only Windows has taken 13GB of hardisk space so if you have a 20 GB hardisk its better to add another hardisk or upgrade your disk.

Then Finally to your question Yes you can make another partition to your existing hardisk by using a software called Partition Magic. You can get a trial copy from www.download.com or just click the link below

http://www.download.com/Paragon-Partition-Manager/...

yea once you have made another partition depending on the version of Vista it will give you option to choose which operating system you like to go on.

If you want to keep those programs so badly, why even bother with Vista?

On to the actual question,

you can't create the partition on your C: drive, unless you reformatted it, at which point you'd partition it into two logical drives.

I'm not sure 20GB is enough; but I've heard from unreliable sources no. it would prompt you on startup, yes.

What I'd do: Either not invest in Vista or get another physical drive for anything that needs to kept and can't be reinstalled, reformat and repartition.

Though I lean heavily towards the former

I know that with the Windows Vista disc, you can create a partition but 20 gb isn't enough (you need at least a 40 GB hard drive for Vista)