I think you can buy specific archival DVDs/CDs that are supposed to last longer than standard ones.
First link from Google. I've never bought them myself but would consider them in the future.
It is also a good idea to use a pen or marker that won't affect the integrity of data on the disk. "They" say the proper way to store them is in a jewel case, in a cool dark place, standing vertically. Not lying flat. Don't know why.
I have pretty much everything backed up to DVDs. Music, pictures, all my important documents, log book scans, scanned certificates (birth, drivers license), etc...
I also have 2 external hard drives, which get updated regularly. I learnt a very important lesson after falling victim to a hard drive failure last year. Luckily, I didn't lose too much, but it put it all in perspective.
Backup, backup, backup!