scan disc probs

Right then Mr Cyber Cat.
You seem to know what your talking about lol, see if you can help me with this one then.
Some time ago I tried to run a scan disc, as your supposed too. You know when you set scan disck to run at the next start up? You can put ticks on 2 little boxes that say summat like, attempt to repair errors and something else. Well I did that, as I always do and it was set from the next time windows booted up. Thing is, ever since then, all I get at start up is,
“cannot open volume for direct access, Windows has finished checking the disc” then it just boots up, allbeit slowly and off we go. I can run a scan disc if I leave the 2 boxes Unchecked and defrag is ok. I,ve run virus scans and also have spyware doctor..which although good is actually a bit of a pain because it always tries to load when windows starts up which makes booting up take bloody ages. I aslo keep getting anoying screen freezes. Is there a way to get out of a screen freeze without rebooting all the time? My OS is windows xp 2 home btw. And one more thing lol. I dont have my beloved norton antiv virus installed, I,ve got some other make, which is perfectly adequate, but it takes 3 hours to do a virus scan for a start. Thing is, I have tried and tried to install norton anti virus 2005 on my pc and it wont let me. A while back I had to do a complete clean installation and after I,d reinstalled my bt broadband I tried to install my norton, but it simply wont do it. Why? I like norton, i,ve always used norton, when I had my old windows 98 machine. I think thats it, end of probs for now. Any help, greatly appreciated. I darent ask PB again lol, for one thing he,s on his hols and for another, he spent at least half a day on the phone to me once helping me sort out my java so this would deffo be pushing it lol. Cheers.