I was trying to change my Windows Explorer appearance using some things like this. This involves replacing system files such as explorer.exe and explorerframe.dll. When I was installing one theme I messed up somehow and disabled dwm.exe (the theme apparently required it). I just ignored the problem and started using the basic windows 7 theme instead (no transparency). Today I tried switching it to the Windows 98 style theme, and that made it so Windows explorer crashes when I try to start it up (except for the taskbar). I can't switch it back because I can't open explorer...is there some way that I can reset those files that are messed up? Thanks
hit win-r , then use that then use that to run
You then can use sfc /scannow (with a install cd, or file caches on the system itself - if you have a i386 folder) to restore the default files.