Is there a way I can make it so that when I view an email on my iPhone?

It marks it as viewed on my computer with all my mail accounts?

I "seems" like it does this with my gmail (although I can't tell) but with Hotmail and other mail accounts it doesn't do this.

Is there anyone that knows if there's a way to make it so that it will do it?

Check your email settings.

If you use the iphone mail app, it should be marked as read on your computer. If you use downloaded apps like the gmail app and the hot-mail app it probably varies.