Check Disk and how long should I wait for it to finnish?

I recently had xp crash and say it has missing or corrupt hal.dll. I tried to repair by popping in XP to use recovery tool, but when it is supposed to ask for password it just shows C:\ then I tried to expand to copy file, it says access denied. I tried chkdsk and went to 25% and finished saying “an error occurred during directory enumeration”. I also tried to do a list using bootcfg /list and couldn’t get any info. I finally took the hard drive out to access it from another machine. Because I wasn’t present at the time of bootup I missed canceling the chkdsk. It has been running ever since. I want to know if I can just reboot and up that I can use data recovery software to recover data and start over or should I let it run?:confused