System particulars:
Athlon XP2000, 512Mb RAM, running Windows 98SE on a DFI Lanparty motherboard.
60Gb and 120Gb hard drive attached to primary IDE channel
CD-RW drive (LG 16X10X40) and DVD-RW drive (Pioneer 104) attached to secondary IDE channel, w/the 104 as the master.
200Gb HD and LD DVD-ROM drive attached to tertiary channel.

Here's the problem: Neither of my burning softwares work properly any more... but they each screw up differently!

Prassi PrimoDVD (which came with the drive) used to burn correctly. I'd select "data disc", select the DVD-R burner, then add the AUDIO_TS and VIDEO_TS directories to the job, and go. But now, all of a sudden, it's turning out coasters that won't play in my Apex AD-1200 anymore. Setting it to "burn and verify" causes the disc to fail verification about 99% of the way into it. (And this happens even with a video which was <1Gb, total, so it wasn't a problem with burning out to the very edge of the disc.)

ULead DVD Workshop will burn them fine, as long as you only burn one copy, close the "burn" window, then go back to start and re-open the burning window again. (I should add, at this point, that I'm trying to turn out multiple copies of an original composition for resale at a sci-fi/fantasy convention.) Telling it to burn multiple copies results in the first copy being OK... but burning the second copy takes twice as long as the first, and a visual inspection of the disc shows that it has burned twice as much data. Then, the third disc takes three times as long and has three times as much burned area, and the fourth...

Now, if only one burn program was screwing up, my first suspect might be a bug in the program... but when two entirely different ones screw up? Especially when they used to work correctly? (I can't imagine what's changed, as I haven't installed anything new on that PC in months and it has no connection to the internet.)

Anyone got any ideas?