windows won't work

i was doing some cleanup,installing some updates, uninstalling some games, defragmenting, things of that sort, restarted my computer when i was done and ran into major problems. when i started up i got as far as the user screen but when it tried to load windows i got the error message cannot find browseui.dll. when i clicked ok i got a black screen with no icons, no start button, no task bar. the same thing in safe mode. i could access task manager and get a command prompt so i downloaded browseui.dll to a flash drive and copied it to my computer, then restarted. i got to the same point and got the application error 0xc0000142. so i just shut it down. the next time i started up, it ran chkdsk and deleted the file normaliz.dll and i'm getting the same situation i had with the first dll error. i am running vista. when i put my disk in, nothing happens. there's really not anything saved on there that is irreplaceable so if i have to start clean it is not a problem.

thanks in advance

 

Thank you for the information but that didn't help. I switched on my pc, and inserted my disc quickly just like it said but still nothing happened. I think my best bet would be to make the disc run from a command prompt. But I'm not sure how to do that.

 

Thank you very much for your help. That worked perfectly. But now I have a new problem. I booted from the disk and did a repair but that didn't work. So I went through again and chose install now so i could start from scratch. I re-installed drivers for my hardware. The computer worked fine for a little while then it went to a blue screen. It said that windows encountered a problem and has been shut down. At the bottom of the blue screen it says collecting data for crash dump. Then it says dumping, with some numbers next to it, and says please wait while your computer restarts. When it tries to restart, windows does not start properly and it goes to the screen where you choose safe mode or start normally etc. The timer counts down and it attempts to start normally but it doesn't start properly and just goes back and forth like that. I did the repair from the disk and eventually had to star clean again, only to run into the same problem. Please help!