Windows Defender & Security Essentials Issue

I have Vista Ultimate and I used to have Windows Defender running until I
recently installed Security Essentials; I noticed that Windows Defender was
no longer running. Several times I reactivated it, but for some reason it
keeps turning off.

Question1: Does Security Essentials disable/turn off Windows Defender?

Question2: If "No" to question1, could you please tell how to keep Windows
Defender enabled/running, or is it not necessary to have both Security
Essentials and Windows Defender running at the same time.

I have searched Microsoft's websites endlessly to get an answer to this
question. If Security Essentials does in fact turn off Windows Defender or it
is not necessary to have both Windows Defender and Security Essentials runing
at the same time, may I suggest that Microsoft advertise this on the Security
Essentials website/webpage somewhere.

Snip from wiki article follows link:

http://en.wikipedia.org/wiki/Security_Essentials -- Microsoft Security
Essentials (MSE) (previously codenamed Morro) is a free antivirus
software created by Microsoft that provides protection against viruses,
spyware, rootkits, and trojans for Windows XP (x86[2]), Windows Vista,
and Windows 7 (both x86 and x64[2]), free of charge.[3] MSE replaces
Windows Live OneCare, a commercial subscription-based antivirus service
and the free Windows Defender, which only protected users from adware
and spyware.

this should answer and fill in the blanks..

Windows Defender and Microsoft Security Essentials
http://social.answers.microsoft.com/...f-0dcedb9ab9fd

Q: How is this different from Windows Defender?

A: Windows Defender detects and removes known spyware only. It is not designed to protect against the full breadth of malicious
software, and specifically does not prevent viruses, worms, Trojans, and other malicious software from infecting your machine. The
new no-cost solution will be a comprehensive anti-malware solution.

Q: Is Microsoft Security Essentials designed to replace Windows Defender?

A: No but if you are running Microsoft Security Essentials, you do not need to run Windows Defender. Microsoft Security Essentials
is designed to disable Windows Defender in order to manage the PC’s real-time protection, including anti-virus, rootkits, Trojans
and spyware.

Q: Does installing Microsoft Security Essentials disable Windows Defender
A: Microsoft Security Essentials should disable Windows Defender on Vista and Windows 7 and uninstall it from XP. In some cases,
this does not happen automatically.
Q: Do I need to manually disable or uninstall Windows Defender if I am using Microsoft Security Essentials?
A: If Microsoft Security Essentials did not automatically disable Windows Defender on Vista or Windows 7, you should disable it to
prevent conflicts. Windows Defender cannot be uninstalled from Vista or Windows 7.
If Microsoft Security Essentials did not automatically uninstall Windows Defender on XP, you should manually uninstall Windows
Defender via Control Panel/Add or Remove Programs.

Q: What happens if I do not disable or uninstall Windows Defender if I am using Microsoft Security Essentials?
A: If Microsoft Security Essentials and Windows Defender are both running, your system may experience performance degradation and
other problems caused by the conflict of two services providing real time protection simultaneously.

[jrivas26]

I have Vista and I used to have Windows Defender running until I
recently installed Microsoft Security Essentials; I noticed that Windows Defender
was
no longer running because I tryed to modify the stratup programs ( due to slow performance). Several times I tyed to reactivated it, but for some reason it is impossible ( error 0x800106ba). So ....Also I couldnt disable Win Defender ( it change from disable to automatic itself).

Question1: if Security Essentials disable/turn off Windows Defender...How can I change the startup programs?

Question2: Is that problem causing my computer running slow?
or I have to uninstall MSE and buy other Antivirus?
There is a program ( RegCure) to fix Win Defender problems...Do you know something about?