I use studio 8 for promotional dvd's and have found it real easy to use. It can be a bit tempramental and need reloading (especially when it comes to the burning process) but for the price, I can recommend it
I use Pinnacle Studio 8 - and like it. Can echo Nick 1's comments that it can need reloading sometimes to keep it working (although I havent needed to for some time, so perhaps one of the patches they released fixed this).
It's mostly very intuitive, the only area I have trouble with is creating bespoke DVD menus (although using one of the built in menus is fine).
Make sure you get the full retail version and not the SE version which is bundled with some products. Although very similar the SE version doesnt allow some key features
I find Studio v8 an excellent easy to use product for simple video editing tasks (capture, dividing captured video into scenes, building a story board, adding titles). It causes problems with burning discs but if you use Studio to create the files then use Nero 6 to burn the DVDs, you will have a fine combination.