There are lots of things you should and shouldn't do to your Meta tags. Below are ten ways that could help your search engine rankings just by optimizing your Meta tags.

1. Don't stuff every word you can think of in your keyword tag. Search engines can penalize you for this by giving you poor rankings. Keep between 10 - 15 keywords/phrases; too many can dilute the effectiveness of your keywords/phrases.
2. Don't put words in your keyword tag that have nothing to do with your site. If caught (and most are) you can be penalized.
3. Don't repeat the same keyword more than 3 times in your tags (esp. the keywords tag), including words in all tenses, for example: run, running, ran. Search engine robots and spiders can pick those kinds of things out. The more you repeat, the less effective the word becomes when it comes time for the search engine to rank your site.
4. Don't exceed the maximum number of characters or words for your title, description and keyword tags.
5. I wouldn't use Meta refresh tags on pages you plan to submit to search engines/directories. Some search engines, like Infoseek, may not index or may give you a poor ranking on their search engine. Infoseek especially, is one who likes to follow links by itself, it doesn't like to be taken somewhere automatically.
6. Your title and description tags are very important also. I would suggest that you put your main keywords and phrases in these tags.
7. Use keyword phrases between 2 to 3 words long. One word keywords tend to be more competitive and aren't usually as effective.
8. Place your most important keywords/phrases at the beginning of your title and keyword tags.
9. It's a good idea that your title tag is the first tag in-between the head tags on your pages.
10. Last tip, if you have a page that you don't want to be indexed, use this tag: META NAME="ROBOTS" CONTENT="NOINDEX" However, not all search engines support this tag. A way around this is to use the robots.txt convention of blocking indexing; most of your major search engines support this.

With a little bit of time and elbow grease you just might be able to turn a sluggish page into a major traffic hub! Do be aware that each search engine is different, so what might work on one, might not work on the other. You might have to change your keywords around a few times in a different order to get the results you are looking for. Of course, Meta tags aren't the only way to help get your site ranked high, but they are a good start.