In response to Charic4 - In order to access Picasa, your blog should be associated with a Google account. If it is not, change the e-mail address of your blog to a G-mail address.
Now log in to your blogger account and launch a page from your blog. Next click on the edit button. This will open the edit function. At the top you will find a link via which you could add an image to your blog. Clicking on that, will cause a box to open out in which the upload functions are found on the left column. Click on the option "From This Blog."
When you do so, some thumbnails of the images that are on your blog will become visible. On top you will find the phrase "These images are also available to view and share in Picasa Web Albums, Google's free photo hosting service." On this phrase itself you will find the link to Picasa Web Albums, which being a hyperlink, will be in blue.
Clicking on this will display the all your albums on Picasa. Clicking on the image of one of these albums will show all the images in that album. Click on one of those images and you will find the option "actions" on top with a drop down menu. On that drop down menu you will find the command to delete that particular image.
John Pitt has explained (above) how you could select multiple images to delete. Thanks for the tips given by Jim.Sheng and Livewirez I was able to access Picasa and discover how to delete images that I had uploaded to my blogger blog.