The Temporary Internet Files (or cache) folder contains Web page content that is stored on your hard disk for quick viewing. This cache permits Internet Explorer or MSN Explorer to download only the content that has changed since you last viewed a Web page, instead of downloading all the content for a page every time it is displayed. To delete the files in the Temporary Internet Files folder, follow these steps:.
1. Quit Internet Explorer and quit any instances of Windows Explorer.
2. Click Start, click Control Panel, and then double-click Internet Options.
3. On the General tab, click Delete Files under Temporary Internet Files.
4. In the Delete Files dialog box, click to select the Delete all offline content check box , and then click OK.
5. Click OK.
there is no real benifit in keeping these files, you can delete them.
Hope this Helps,