Black screen after boot

First of all, I don't know if this is the right forum, but none of the other forums looked like the right one so I posted here. Feel free to move it or whatever. Also couldn't find the answer anywhere else so sorry if this is a repost.

Okay, so last night I tried installing Microsoft Security Essentials, and upon reboot, the windows login screen is okay, but after logging in, it takes me to a black screen. No taskbar, no desktop icons, no start menu. I AM able to ctrl+alt+del and run programs from task manager (such as msconfig, services, etc).The mouse cursor also is available. I was able to get MSE uninstalled but still no luck, even in safe mode.Still a black screen with no taskbar, no start menu, no desktop icons... it's as if the desktop itself can't open. Also i currently have no antivirus programs as I uninstalled them before trying to install MSE. System Recovery didn't seem to work either. Any ideas as to what to do to resolve the issue?

Also, I tried running explorer.exe but that brought up "Computer" (showing all the drives and such) instead of running explorer.exe. Something wrong there perhaps?

I can't post my computer specs since I can't access my pc to type this, but I'll repost my specs from my last thread.

Thanks in advance

The one option you can try to see how far you get would be booting live from the 7 installation media if you have a 7 dvd or USB Installation Key and this is not simply a preinstalled copy of Windows without any recovery media onhand. Once you reach the Install Now screen look below for the repair tools link and select the System Restore option. That will allow you to select a valid restore point to bring things back a bit before this came up.

To this correctly follow the steps in the guide for this using Option Two seen at System Recovery Options Hopefully you have a good point that will only take you back a few days maybe a week or so available.

If 7 came preinstalled with the original board going belly up on you the only move you could make would be going back to Asus to see if they still have an exact replacement or buy a new license! The OEM key to tied to the original hardwares the HP came with there!

What that means is since you made a major hardware change the key is no longer usable and a new 7 purchase by electronic sales(download only) or finding a good deal on even a retail full or upgrade set or an OEM for System Builder single installation dvd would be needed to put a clean install if you are unable to get 7 activated by entering the new key.

Again once you do that your best move is to plan a clean install to start fresh and then restore the WETransfer backup once you have all the same programs on again which will solve any number of problem simply trying to keep the same preinstalled copy of Windows running. When you are simply working with the same hardwares the DISM then can work out without any problems. You are using the exact same hardware profile and device drivers. The registry is also in good shape as well.