Seabody, it's good to make a backup games onto CD (I think you mean DVD right?). And if you compressing it, and in case you're using Winrar (google it), you should put a "Recovery record" to protect your files when compressing. And of course, about your 2nd question, the answer is "NO". Here is what you need to put a "recovery record" when compressing your files (in case you're using Winrar):
1. Right click on the folder you want to compress.
2. Select "Add to archive..."
3. A Winrar window will appear, and in the "General" tab, you will see a checkbox called "Put recovery record", just check it and you're done.
In additional, if you want to split your folder, there's a box called "Split to volumes, bytes" there too. Type in number of bytes you want to split per file (rar file when complete) and you're done.
Good luck and happy simming
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