Hello,
The launcher crashes because of JScript errors in the webpage it displays. It uses an old Internet Explorer engine, which doesn't get along with newer JavaScript.
The easiest workaround to stop it from crashing I found so far is is to prevent it accessing the internet. To not have to disconnect completely from the internet you can tell Windows Firewall to not allow it through. In order to do that, follow these illustrated steps (click the link below for a screenshot):
1. Start the game and have the launcher crash. DO NOT yet hit "Close program". We'll need it still open to find out which of the many launchers installed with the Expansion Packs is used and where it's installed.
2. Open Task Manager by right clicking on an empty spot on the task bar and clicking on "Task Manager"
launch_taskmanager.png
3. Right click on the entry for the launcher and click "Open file location"
task_manager-open_file_location.png
4. Windows Explorer will now open and highlight the executable of the launcher. Hold down shift and right click on it. Click on "Copy as path".
copy_address_as_path.png
5. Hit the Windows Key and enter "Windows Firewall". Click the entry it'll find. In the left pane of the window that'll open is an entry "Advanced settings". Click it!
open_advanced_windows_firewall.png
6. Again in the left pane of the opening window, right click on "Outbound rules" and "New Rule...".
firewall_create_rule.png
7. Choose "Program" as rule type and click "Next >".
new_firewall_rule-type.png
8. Right click into the field below "This program path:" and on "Paste". It will paste the path to the executable we copied in step 4. The path will be surrounded with double quotes ", though the firewall wont like that, so remove them. Click "Next >".
new_firewall_rule-program.png
9. Choose "Block the connection" and click "Next >".
new_firewall_rule-action.png
10. To keep it simple, make sure the checkboxes for all, "Domain", "Private" and "Public" are checked. Click "Next >".
new_firewall_rule-profile.png
11. Now we need to give the kid a name. "Sims 2 Launcher" should do fine. Hit "Finish".
new_firewall_rule-name.png
Now it's time to test it. If you try to start the game again it should open the launcher and the window will be a little shorter because it doesn't have the web browser embedded anymore. You should now be able to launch the game just fine.
I hope this helps and was easy enough to follow 🙂.