Yes, all these things are possible with some knowledge of CSS.
I recommend you start with the CSS style sheet supplied (link it into the <head> section of your page), and then add additional styles to achieve what you want.
If you need assistance with CSS, we can provide you with a quote for this work.
The other option is to use a complex HTML editor such as DreamWeaver to create your page with a form the way you want it to look, and then use the Configuration Wizard's "Convert a form" feature to adjust the form so it works with FormMail. This doesn't change the look of the HTML, just adds hidden fields and other elements so it will work with your configured FormMail.