So i did everything as per the first youtube clip however i encountered some problems:
1) couldnt find Library and thus application support. Found it was a hidden folder (press shift/command/g to get "go to folder" and type ~/Library and its all in there)
2) still could not transfer themes
So what i did was download some free themes from www.dvdthemepak.com/
After doing this iDVD worked!
Click on the grey themes below those that are available and iDVD autamatically updates them.
To get the themes that were in the original files of iDVD, i went to application support (directions above) and found that an iDVD had autimatically been added. I simply transfered the contents of the folder iDVD 6 (as per the first youtube clip) into this autimatically created folder.
Very long winded i know, but saves buying iLife and handing over more unnecessary $$$ to the very same people that removed iDVD in the first place.