|The laser that reads and writes CD media is the same laser. Combination drives have two or more lasers because the wave length used for CD, DVD, blueray are all different.|
The laser intensity varies with the task. Burning requires a stronger laser beam.
There are a couple of likely causes for your problem. One is the lens over the laser is dirty (sooty). This may be corrected by using a lens cleaner or by disassemble and using a Q-tip and alcohol.
Another possibility is the laser is wearing out and is no longer powerful enough to perform a clean burn.
If you have a desktop computer I suggest you consider replacing the drive. I consider optical drives to be disposable hardware. You can buy one for about $20.
You do need to know if you have what type of drive interface (IDE/SATA) you can use. SATA is easier to find so is you have the capability to use that type then that is what I would suggest.
Occasionally, a different brand of disks can cause issues and if you are reusing a CDRW disk it can be at end of life.
BTW, you need to add RAM to your system. 256MB with WinXP is not enough.