FIlling in job application form: is it ok to scan it and fill it in using a computer?

Probably, but much better to do it by hand. Creates a better impression. Just take a little care.

Part of the application process may be to check on your handwriting and drafting ability. I'd check to see if the application form is available online (especially if it's a large employer), so that could then be completed by typing. The employer may be looking for someone who can follow instructions. If you then ignore the instruction "fill this form in your own handwriting" then they may not invite you to interview. what ever you do DON't write on the form "See attached CV/resume" That indicates you are lazy and again can't follow simple instructions. Remember applying for a job is a game played to the employers rules. If you know you have poor handwriting i'd copy the form several times and practice practice practice. Good Luck with your application!

I have always been told to make my job application very good quality, do what makes it look the best. Here is also a tip, use good quality paper, it just makes it "better". ;)