Bulk File Uploads to SharePoint shown as Checked Out in WSS 3.0 and MOSS 2007

Issue: You are uploading multiple documents to your SharePoint libraries via the built in multiple document upload capability or through an explorer view. After uploading these files you notice that all these recently uploaded files are marked as checked out and you must manually click "Check in" on each document. This is time consuming and you want to avoid the issue with future uploads.
Background: This situation is related to a versioning setting in your document library.
Suggested Resolution: For the library in question where you are having this issue, do the following:
Navigate to the library then go to > Settings > Document Library Settings

Next click on Versioning Settings

Next Change your settings to require No Versioning, do not require documents to be checked out and then finally click OK to finish

OR --- FOLLOW THIS

Well, there is a simple solution for this: "Site Content and Structure"
Go to Site Actions-> Site Settings -> Under Site administration, you'll see the option "Site Content and Structure"
You can also go to this page by appending the text as shown in following URL:
htp://YourSite/sites/_layouts/sitemanager.aspx
Now in this, navigate to the document library from left side -> and now in main view, select all the documents which you want to check in.
Click on "Actions" from the top and say "Check in" 
Isn't it is simple.!