I believe that insufficient RAM may be the source of some of your problems. If you have a RAM of somewhere 4 to 8GB, you will experience smoother computing. 3GB doesn't seem right, so you might want to learn more by going to this site:
I don't know what know what's happening with your optical drive, but it seems you use your drive quite a bit. In that case, look into a lens cleaner for your machine. It's inexpensive, works quite well.
I hope you'll post here with your results!