I like the idea! It would indeed be useful, to get an email reminder. Of course, the person would have to take into account how often he/she checks his email. But, overall, a good idea. The info on the front page is simple and direct. Just one minor warning on the info on the front page:
This service is great!
Yes it is!
That might sound a tad egotistical. You might want to be aware of that.
Okay, now for the real problems. Looking at the page itself, it seems too dark. I believe changing the text color to white would be a big help.
Now, looking at your source, that is where we run into real trouble.
First off, a couple of validation errors.
<img src="/images/spacer.gif" width=10 height=74> That should have an alt attribute. Also, it wouldn't hurt to have quotation marks around all attribute values. (width="10" height="74")
<table id="tblHeader" cellspacing="0" cellpadding="0" border="0" width="698" background="/images/Title.gif">Background as an attribute doesn't work with this tag.
But those two things will be rendered moot with what's coming up.
I see you have a cascading style sheet, so that should be used to replace the tabular layout. Takes up a LOT less room, I promise you. You've got a lot of nested tables, and you'll run into problems with that, especially when it comes to bandwidth. Considering you're offering a FREE service, you'll want to keep a very close eye on your bandwidth costs.
In your CSS, you have class and id names that don't seem to make a word. It may help to use words to remind you precisely what those ids and classes do.
I'm not all that good at cascading style sheets, but I know a lot of people here can help you with converting your tables into a CSS layout.
If you have different layouts on other pages, don't be afraid to create a second external style sheet. I've got a dozen of them (okay, 11) in my own website, and then I've got internal style sheets here, there, and everywhere.
Another thing about replacing tables with a CSS layout, is accessability. Someone who is blind would not be able to make sense of so many tables. If you used a CSS layout, it would be completely ignored by a screen reader, or a tactile moniter (A moniter the blind can feel), but you would still have a usable website.
Lastly, a suggestion for your signup sheet. You may wish for a "confirm Password," so that people can be sure they wrote down what they REALLY wanted, instead of having a typo in their password.
Again, you have a good idea, and I'm giving you suggestions so you have a website to match. :)
UPDATE:
Looking at your website, I think I could give you a few pointers myself. :)