DVD Backup on MOdded PS2`
 

how do i play backed up DVD movies on a modded PS2. is that possible?

if its a DVD movie then you dont even need a mod chip just put in the movie and it will play

Yep, just use good media.

so the ps2 will just read the DVD-R backup without any issues?

That is correct. As long as you burn them properly and use good media like already stated.

as long as the disc is put on good media

I know this getting a bit repetative but you gotta love those ridata G04's. :p
Use Ritek brand media. That should solve your problem in regards to media! ;)