HTML Depreciated In Internet Explorer 10 Versus Previous Versions

In hopes of solving some issues I was experiencing with IE-9, I upgraded to Pre-Release 10. Anyway, now that I'm on IE-10, I've noticed that some webpages I've written no longer appear the way I'd like them to. Specifically, this relates to tables; more specifically, to their borders. From what I can tell so far, this is due to the fact that IE-10 has deprecated the following HTML tag: bordercolor="value". I've considered the idea of reverting back to IE-9, but rejected that as a misguided attempt to hold onto the past: i.e., I think other browsers have already deprecated this tag; IE-9 being the last hold-out.

So onward we go. And from what I can gather, the way forward will involve some kind of CSS implementation, about which I know almost nothing; something I'm not bragging about, to be sure. I've begun to review some online documentation, specifically, HTML Dog. While this seems like a great resource, I'm having a hard time using it to quickly learn how to make the necessary changes to some production webpages so I can restore them to their previous appearance. Perhaps, I should mention that I really don't use any special webpage generation tools. I just write the straight HTML code using MS Wordpad. Also, my knowledge of HTML is both rudimentary and backlevel: what I've learned to do over the years is probably based on the HTML 3.0 standard.