I received a DVD-burner for Christmas (thanks, Mom!) and have been researching the difference between the various standards (plus, minus, DVD-RAM). I came across the following article which gives a good explanation in plain English. Check it out if you are trying to figure this out yourself.
AnandTech View FAQ
And while you are at it... make sure to get a recorder that writes to both plus and minus discs. This will give you flexibility to buy whichever media is the least expensive at any given time. Currently it looks like the minus discs are cheaper than plus discs.