I spent some time modifying a client's cart page regarding the Gift Wrap option today. I've always found the default to be obtuse and not clear about what the customer is supposed to do (e.g.: Gift Wrap - Qty: 0 - $0.00 /each).

I am attaching a screenshot of what the gift wrap verbiage looks like in the cart, and the instructions in a text file. You can edit the verbiage to your needs of course, but thought I'd share.

Also, for what it's worth and what I found from other posts: Gift Wrap is turned ON by default, and DISABLING it through Options | Gift Wrap appears to not have an effect. From what I've read, it is only possible to globally disable gift wrap by doing a bulk/batch inventory update (but I have not performed this).

In a nutshell, I modified cart.aspx, cart.aspx.vb, giftwrap.aspx and then added a style on styles.css for the color/border around the gift wrap options on the cart page.

Hope this is of some use...
Shelly Z aka idahogrrl