Most of the windows users encounter some or the other problems related to their computer. It may be hardware or software related problems. Always it is better if you could manage to troubleshoot the basic problems on their own. Here are two free software tools collection CD's recommended to have which helps you to troubleshoot problems related to hardware and software.
Hiren's BootCD : This CD has good collection of very useful tools and utilities related to backup, filesystem, antivirus, hard disk, network, tweakers, memory testing, system information, security and encryption, registry, remote accessing, data recovery, password, partition and many others. Click here to read more.
Ultimate Boot CD: This CD consists of tools related to hardware such as BIOS, hard disk, data recovery, partitioning , boot management and other hardware peripherals and other hardware related. Click here to read more.