I was in this same boat about 3 years ago when I first got my mac, partly for this very purpose. I wanted a self contained, easy way to transfer Vhs to DVD with user friendly software. 3 years later, I'm still trying to figure it out and am finally on my way.
First, as the others mentioned, you will need a DV converter. I just bought a Canopus ADVC 110 and it works pretty slick. As the others mentioned, it is possible to use a DV camera to import the video directly to Imovie, but it sounds like in the UK you may have issues with cameras.
Another thing to consider is what software to capture the video with.
I wanted to use Imovie because it was easy and in the Mac to begin with, what I found out after many forum questions and experimenting at home was that Imovie, at least the version I have, only imports every other line of resolution of the videos. So when I captured a home movie from my video camera into IMovie and then used a software program (I used Toast) to make a DVD it looked like garbage on my TV. The verison of Imovie I have however is 08' (I think) so I'm not sure if the new version imports better quality now. I would check on that before you capture/import all your vhs into Imovie only to find out it's going to make your home movies look awful on a TV.
To combat this, I had to get Final Cut Express which I am now finally starting to learn how to use.
Once you determine how you are going to get the videos onto the Mac, either DV Converter or the right camera, then you need to decide if your Imovie will give you the right output of image quality, then burning the DVD's isn't too bad.
IDVD works pretty slick and there are videos you can watch on the Mac website that show you how to use it.
Like I said, I've used TOAST a few times and it's pretty easy and user friendly as well.
Hope this helps a little.