Question for DVD Burning Gurus?

I am getting ready to buy a DVD burner for my computer so I am a newbie at this. I am going to back up my movie collection. My question is this, do you lose much video and/or audio quality when you burn an original dual layer movie onto a compressed single layer disc in order to avoid having to use 2 discs for 1 movie? Also what software would you recommend for burning dvds? Thank you for your help.

Save yourself a lot of grief and forget about the DVD burner for your computer. Buy yourself a DVD recorder - the current Sony model with the firwire input is a good choice - and save yourself a lot of misery dealing with software glitches, on-line manuals written by people that flunked college english, downloading drivers, etc.
With the exception of "authoring" type DVD burners (that cost several thousand dollars) - ALL of the current consumer grade DVD burners are identical to the ones used in standalone DVD recorders. And just as important, unless your DVD drive is properly grounded and shielded, it will create discs with unwanted audio and video noise.
The nice feature of the DVD recorders is that they can be used to replace your VCR. All of them have tuners - usually of better quality than in your VCR - and can not only write on one pass DVD-R or DVD+R discs - but can also record to re-writeable DVD-RW and DVD+RW discs that you can use just like a tape to record TV shows on. Also, they can serve as a backup CD player and DVD player in a pinch.
The price of recordable DVD-R & DVD+R discs continues to drop - with the latest batch my studio bought costing less than $2.50 a disc for top of the line Maxell DVD-Rs. Take it from someone who makes discs for a living - DVD burners are considered as strictly "amateur hour" in my industry.
DVD recorders cant copy a dvd!
That said, the best software out there is DVD X COPY, and
DVD X COPY Express. The first one will copy bit for bit and in 5.1 DD or DTS, but most movies require 2 discs.
DVD express will remove all special features and secondary
soundtracks but does compromise video quality a little with thier compression scheme. I own and use both.
Good Luck!
Agree with both of the above post. I bought a DVD burner with the expectations of copying my movies. ItÂ’s not worth the hassle. I will use my burner for data back up, digital pictures and digital camcorder. I also thought I would copy TV shows with my ATI video card and then burn them on a DVD. Again- bad idea. The ATI card is just too unstable and unreliable and the recording looks awful.

Avideo I'm curious what the "tuner" does that you refered to in DVD recorders. How do you connect the recorder to the tv signal? Through the processor?
Lokie, Avideo is referring to a dvd recorder for home use, not a dvd burner for computers. Just like a vcr the dvd recorder has a built in tuner.
Vader007; I realize that he was referring to dvd recorder. When I said processor I meant the AV processor or preamp.
Excuse my ignorance but I don't know what a tuner is or does in a VCR or a dvd burner..
Sorry Vader, but if you use the S-VHS output on your DVD player and connect it to the S-VHS input on a DVD recorder, it will make copies just fine. Keep in mind that most DVDs
have about 450 lines of horizontal resolution - which is about the limits of what a S-VHS video connection will pass.
In addition, ALL DVD recorders have a video noise reduction circuit which "cleans up" virtually all video noise on DVD recordings. So DVD copies made this way, have little or no loss of detail from the original.
Sorry Avideo, I dissagree. You are going through four conversion stages using an s-video output which will degrade to recording a lot. I was referring to a direct bit for bit digital transfer. "Just fine" maybe for you, but dont mislead others without giving them the whole truth. Also interlaced performance is nowhere near progressive so dont feed me that 450 resolution crap either.
Thanks to everyone for your replies. It has really helped this newbie.