IMG-Tags work fine with IE, but not with FF

Hi there,
first I have to say thanks for that great theme ... I really love it! :-)

Normally I use FF, and I was wondering why the IMG-Tags like this <img width="130" vspace="5" hspace="10" height="120" border="1" align="left" src="/wissen/Rassenbilder/Brandzeichen_bayerisches_wa.jpg" alt="Brandzeichen Bayerisches Warmblut" />) are nor working. Everythin seems to be fine in IE, but in FF the hspace, the border and the vspace aren't appearing.

I also have to say, that I'm not very confident with this stuff, I'm a typical beginner.

Do you have any advice for me, how to fix this? Because most of my users use FF instead of IE, and the look without vspace and hspace is not the best.

Thanks for helping :-)
best wishes,
Sabine