i am a new girl in dreamworld please help me...

[MADFORIT]

Igorage

Burning speed should make no difference to whether or not your CD works in your DC. As long as the CDR you are burning to, and the software/system, are up to the job.

I think, maybe, you have not got the full version of Discjuggler 3, therefore it only allows 1x write.
Get the full version, or get a serial number for your software, try searching the Internet for it.

As for media types, use whatever you think works best, I do, I use unbranded 74min & Discplanet 80min CDR.