Contact form suggestions

Hi,
I'm looking to put together a contact form.
Needs to be responsive, with text box, drop down list & upload photo option.

I'm currently using Jotform but having issues as I'm sure the form I'm using has gremlins.

Can you recommend anything please.
I've looked through some pages on here but not to keen.

Thanks.

Ive now started on a form & will be back later for some assistance if i may please.

Thanks

Afternoon all,
I have now completed my form and happy with the way it looks etc,
But could you advise some edits/alterations for me please.

Here is the form below.
Here is the form in question, http://www.theremotedoctor.co.uk/form-contact.html

1,The fields below MUST be completed if not a pop up message is shown to advise the customer to do so.
Name, Email Address, Vehicle Make, Vehicle Model.

2, The field Email Address must have a valid email entered into it, some kind of check so the customer just doesn't type gfibibohgfo because the field must be completed, @ must be present etc.

3, If HONDA is selected from the Vehicle make selection list then show Chassis Number field, otherwise any other selection made please hide Chassis Number field.

4, Chassis Number field must contain 17 characters when customers types in the field,any more or any less pop up message to be shown.

5, I was unable to alter the length of the Chassis Number without it altering the Postage Destination field at the same time,17 characters will be entered but the field looks like it will accept 50 etc.

6, When SEND FORM is pressed i need to specify my email here so i receive it BUT without spam robots sending me junk.

7, Add a very basic security question like "what is 4 + 6" nothing fancy,if total is 10 then send form,anything other than 10 do not send form & show a pop up message, "what do you think"

8, Allow customer to attach / upload a photo to send me.



I do have another 2 forms of which will be based on this form,they will look the same but a couple different questions, but will work from the same css file.

Many thanks for the help.

Just remembered the message box.
I will add that to the firm tomorrow.