Image via WikipediaYou should be able to delete all files with .CHK or .TMP extensions. Files with .CHK extension are created by the Check Disk (Chkdsk) utility, which allows you to examine a hard disk for errors. Files with the .TMP extension are temporary files. Sometimes temporary files are not deleted, as in the case of system failures.
You should not delete files with the .EXE or .COM extension. These are executable files that run programs.
You should not delete files with the .OCX or .DLL extension. .OCX files are ActiveX controls and .DLL files are dynamic link libraries. Both types of files are loaded by executable programs.
You should not delete files with the .SYS extension. These are system driver files. They are required to enable the operating system to communicate with hardware devices.
Disk Cleanup is a Windows XP tool that searches for files you can safely delete. See the link below to see how to use the Disk Cleanup tool in Windows XP.
http://support.microsoft.com/kb/310312
