You need to log in as an Administrator to delete some files.
To 'refresh' (your words) your Windows, you might be better to use System Restore to go back in time to before you started getting the bluescreen.
Get into 'Safe Mode' by slowly tapping F8 as the computer restarts - (log-in as Administrator).
Start > Run > type RSTRUI.EXE > and OK or Enter.
Choose a Restore Point from the list - but make sure it's definitely BEFORE the blue screen started up.
Don't forget to allow the computer some time to do the Restoration as well. It can take a few minutes. It should eventually come up with a message saying whether the Restore was successful or not.
Oh yeah -
If it DOES work and you find Windows is running ok again, then go into System Restore again and switch it OFF, and then switch it back ON again.
Then immediately make a new manual Restore Point so you have something to fall back on.
Doing this will dump all the other restore points which may well still have the virus within them.
This ensures that if you use System Restore again in the near future you won't accidentally reinfect your machine again.
Check System Restore to make sure that you DO only have the restore point that you just made.
By the way, you can also remove individual Restore Points if necessary (except your most recent one - for safety) by using the free CCleaner via Tools > System Restore.
(If you open CCleaner by right-clicking and 'Run as Administrator' - in Vista)
http://www.piriform.com/
p.s.
If you 'refresh' your Windows by doing a complete reinstall, and if you have all your personal files on the 'C' drive/partition alone, then you will lose everything as the computer will reformat the whole drive as it installs a new copy of Windows.
That's why it's always a good idea to make a second partition and move your 'My Documents' folder to that. - which you can do by right-clicking to change its location.
p.p.s.
To delete those files you mentioned you may need to 'Take Ownership' of them first. This tool adds a line in your right-click menu so that you can do this more easily.
http://www.howtogeek.com/howto/windows-vista/add-take-ownership-to-explorer-right-click-menu-in-vista/
Ciao :-)