Unable To Reinstall SQL Server 2005

Previously, I have installed SQL 2005 developer edition simplyfied chinese
successfully. But yesterday, I tried to install mobile client software
factory. The installation process create a database as following:
Create DATABASE [AdventureWorksMobileStaging] ON PRIMARY
( NAME = N'AdventureWorksMobileStaging', FILENAME = N'C:GotDotNetMCSF_728ReferenceImplementationsAdventureWorksToGoDBScriptsAdventureWorksMobileStaging.mdf' , SIZE = 195584KB , MAXSIZE = UNLIMITED, FILEGROWTH = 1024KB )
( NAME = N'AdventureWorksMobileStaging_log', FILENAME = N'C:GotDotNetMCSF_728ReferenceImplementationsAdventureWorksToGoDBScriptsAdventureWorksMobileStaging_log.ldf' , SIZE = 265344KB , MAXSIZE = 2048GB , FILEGROWTH = 10%)
But today, when I start my notebook, SQL server could not be started.

Then I uninstalled the SQL instance by start->control panel->uninstall...The uninstall
process seems OK. Note that I only uninstalled the instance.Then I tried to reinstall
SQL 2005. However it was reported a Performance Monitor Counter registry key mismatch
error occures. I tried to fix it but failed. The problem is as following:

1, The installation process report a warning of low memory.
My notebook has 512M memory. I have reinstalled SQL 2005 once successfully. At that
time, the warning also shows, but it seems that this warning does not affect installation.

2, User type problem.
The OS of my notebook is XP professional, which is upgraded from XP home edition.
I login it using a domain user such as: "my company's domainmyaccount". I found it
curiously that although I assign myaccount as an Administrator, it will automaticly
changed to "SQL$...." account. I don't know why and when the account property is
changed. But everytime, when I found, I will assign myaccount as an Administrator
back.

3, Performance Monitor Counter registry key problem.
To fix the problem, I firstly tried to run lodctr.exe in cmd window but failed.
When I cd to c:windowssystem32 dir, I can ran lodctr.exe correctly.
I check HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindows NTCurrentVersionPerflib,
the result is:
"Last Counter"=dword:0000149c (11128)
"Last Help"=dword:0000149d (11129)
Then I check HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindows NTCurrentVersionPerflib09
and 004, the result is confusing. I can find counter and help key,but both keys contains
really a lot of stuff as:
(1) first page of Counter key:
1
1847
2
System
4
Memory
6
% Processor Time
10
File Read Operations/sec
12
(2) first page of Help key:
3
The System performance object consists of counters that apply to more than one instance of a component processors on the computer.
5
The Memory performance object consists of counters that describe the behavior of physical and virtual memory on the computer. Physical memory is the amount of random access memory on the computer. Virtual memory consists of the space in physical memory and on disk. Many of the memory counters monitor paging, which is the movement of pages of code and data between disk and physical memory. Excessive paging, a symptom of a memory shortage, can cause delays which interfere with all system processes.
7
% Processor Time is the percentage of elapsed time that the processor spends to execute a non-Idle thread. It is calculated by measuring the duration of the idle thread is active in the sample interval, and subtracting that time from interval duration. (Each processor has an idle thread that consumes cycles when no other threads are ready to run). This counter is the primary indicator of processor activity, and displays the average percentage of busy time observed during the sample interval. It is calculated by monitoring the time that the service is inactive, and subtracting that value from 100%.
9
% Total DPC Time is the average percentage of time that all processors spend receiving and servicing deferred procedure calls (DPCs). (DPCs are interrupts that run at a lower priority than the standard interrupts). It is the sum of Processor: % DPC Time for all processors on the computer, divided by the number of processors. System: % Total DPC Time is a component of System: % Total Privileged Time because DPCs are executed in privileged mode. DPCs are counted separately and are not a component of the interrupt count. This counter displays the average busy time as a percentage of the sample time.
11
File Read Operations/sec is the combined rate of file system read requests to all devices on the computer, including requests to read from the file system cache. It is measured in numbers of reads. This counter displays the difference between the values observed in the last two samples, divided by the duration of the sample interval.

I could not find the maximum value of the Counter key and help key, so I could not repair
Last Counter and Last Help key as discribed at SQL 2005 help. Which item correspond to
maximum value of the Counter key and help key?

I tried to correct Last Counter and Help key as:
"Last Counter"=dword:0000149c (5276)
"Last Help"=dword:0000149d (5277)
But it also doesn't work.