Nothing working on my other comp! HELP!

hi guys. Im having a bit of a situation on my other computer. I use that computer for business and nothing currently works on the computer. Everything is still there but as i try to run a program, such as add or remove program, or Microsoft word, it says: Windows cannot open this file. Then it asks select a program from a list or either use the web service to find ther appropiate program. I downloaded AD-Adware SE Professional and used AD-watched. As i was done running the Ad-Adware, it told me to reboot for some reason. As it came back to the desktop, i cant run a single thing on it. Please i need help ASAP and the more information, the more is appreciated.

-surefire1209

 

-Windows XP
-Pentium 4 3.0ghz
-Service Pack 2
-512 RAM
-GeForce 5950 FX Ultra

this started happening just about 20 minutes ago. and for some reason, my mozilla firefox still works.

 

i cant even open it.

 

sorry...how would u able to locate it and open it? i assumed to that because nothing else works.

 

Have you tried running the computer in safe mode yet? This might give you an opportunity to troubleshoot. Maybe even use the computer for work and fix it later.

 

yes i have tried in safe mode. didnt work

 

If you can still surf go here,may help-
http://www.dougknox.com/index.html
WinXP fixes and look for file association fixes.

 

it would help me more if you specifically told me which one because there is a little more than probably 200.

 

Start with the exe file fix first to see if you can get your security progs up and running again.

 

ok as i tried, it couldnt open both. it gives me that error saying windows coulnt open it and either try opening it with program on ur computer or finding the appropiate program by web. The only weird thing is if i do browse for that program and find it on the computer, it actually works.