BleepingComputer.com: CHKDSK

I am using Vista Home Basic with a Dell Inspiron 531 and am having a problem with the check disc utility. I have tried to set up a scan using the command prompt,it won't scan like it says. It says a scan is scheduled but upon restart it does not do it! I triedto access it through the start menu and had luck with scanning the "D" drive but not the "C" drive,The UAC permission box won't appear at the correct time,not ever in this task,for checking the disc,but will on other things. It also says it will schedule a scan after checking the "schedule a scan after restart box",this never happens. When I'm trying through the start menu it will go all the way to scheduling the scan and just go back to the previous page,the "check here for scan" page,where it has the defrag box and 1 more thing,i forgot now, but maybe you get the general ideas.I also just had an upgrade in the memory,if this has anything to do with it! I just don't believe its major,it wouldn't scan another drive if there was,is my feeling,I'm probably wrong. I also have been unticking some stuff in the MSCONFIG,so I might have unticked something I need for this.(I was trying to stop alot of programs from running at startup.)I also says its in read -only mode at the command prompt box when I try this way!! Maybe I have the wrong Mode,we have had the power knocked out here a few times lately. I would really be thankful if someone could help me. Any advise or know how about this?