Help! I can't burn DVDs

[barkroc2]

this problem has developed since changing to vista, but even when i put xppro back on, same deal....now i got vista back on.
every once in a while a dvd works, but for the most part after a "successful" burn the dvd is still BLANK! i dont get it? every burn proggie does the same thing..no errors, just a blank dvd. i should say cds burn/play fine. 2 burners, with both fw's up to date. the only thing i notice diff't is when burning the thing seem to hang longer on lead in/lead out. any ideas??????

BTW THESE ARE ALL ISOS IM TRYING TO BURN