Hi Peter,
Thank you for getting to us with this question!
Of course no need to disturb Eclipse... let it rest :)
Steps to do the same are pretty similar, but it just took me less than 3 minutes doing this, so I believe it's easier than using Eclipse.
Changing the -meta.xml file and trying to build it against the production won't help - Salesforce don't allow this change to be done in a such way, however there's another way:
1. Get your sandbox (* - yup
, details in small font below) project opened with the trigger present there
2. Change the status to "Inactive" in the -meta.xml for your trigger
3. Right-click on the project and select 'Deploy to organization', enter the credentials of your production org and choose only the trigger you want to deactivate and proceed with deployment
Once the previous step is done - the trigger is inactive. If you need to delete it, you'll need 2 (okay, 3) more steps:
4. Right-click on the project and select the 'Project metadata components', find your trigger, uncheck it and apply the changes
5. Again navigate to the 'Deploy to organization', enter the credentials of the prod org and choose your trigger - the "Action" near it will state "Delete". Proceed with the deployment
6. As your action in the 4th step removed the 'Subscribe' mark from your triggers in the project, please open once more the 'Project metadata components' and click the 'Subscribe' button near the 'Apex Triggers'
Might look like "too much steps", but the process is pretty straightforward and works really fast.
Regarding that * in the 1st step - tomorrow (Friday) we'll release a new version of TWS for Mac where you will be able to deploy to the same organization using the 'Deploy to organiation' features and, even, you won't need to enter your credentials. So with the (not yet released) Blaze R9 you'll be able to open/create a project directly for your prod environment and do everything even faster (while with the same number of steps).
Hope this helps!
Best regards,
Vladimir