Nero and others cd burning nightmares

Hi All
Hope someone can offer some help after this week of nightmare.This is my first time of using Nero, decided to try this after this awful week with CloneCD,let me just say I have used CloneCD for many months with no problems until last Saturday when trying to copy a cd on the fly everything sized up, had to restart,no cd drives found,had to restore reg,tried again and able to copy o.k,thought everything o.k then it happened again n again everytime it starts to write it just siezed up so tried Winoncd that got to 46% then did same taking all knowledge of cd drives with it. Now trying Nero 5.5 the same thing happened on trying to copy on the fly but can read to image then write o.k but when writing the used read buffers bar keeps going down to 1% then builds back up this happens when the write is at about 66% is this a problem as I was told that bar should stay at or near 100% both drives are on same cable but that's how they have always been and I could copy on the fly. Any help would be greatly appreciated. I know it's not that important to be able to copy on the fly am more interested as to why these problems.
Win 98se
Athlon 850
512 meg ram
MSI K7T PRO 2-A m/b
Hercules 3D Prophet 2 mx
Soundblaster pci 128
Plextor 12x10x32A
LG 52x cd rom
Many Thanks in advance
lylacwyne