How to change size of the body and sidebar in a wordpress theme ?

Hey guys,



I'm a beginner with wordpress. I could only copy and paste stuff in php, I don't know what css is, or where it's used. :D



I'm doing web development for my first time by doing this webiste

www.umu.man.ac.uk/eee



Managed to add so many plugins, god I love wordpress, lol.



But the thing is, the sidebar and body are very narrow. I need to make the body wider, and the sidebar as well. But I know in some screens, the current width of the stuff is just adequate, so this might be another problem I need to tackle. i.e. I'm using a very wide screen therefore I have so much unused space on the sides.



Also in Internet Explorer ONLY, the post thumbnails, which revolves repeatedly, is too long, that doesn't happen at all in Firefox or chrome.



btw the theme I'm using is called purple rain, here's the link for it

http://www.simplywp.net/2009/10/18/purple-rain-high-quality-wordpress-theme/



Basically my questions are:

1- how to change the size of the body and/or sidebar

2- how to accommodate for different screen sizes/resolutions

3- how to fix the IE bug mentioned above



I'm really appreciating your help, and any feedback and/or suggestions as well.



RegardsHow to change size of the body and sidebar in a wordpress theme ?
I wouldn't go hogwild on the width; there are still people out there with 800x600 screens.



And it's pointless to fix stuff to compensate for IE 6 (and sometimes 7) and their idiosyncratic approach to Web standards. If your stuff passes W3C validation, that should be good enough. (And it should work in IE 8, which does a better job of following standards.)



That said, most of those tweaks are done through style.css, and can be done through the WordPress theme editor.How to change size of the body and sidebar in a wordpress theme ?
1) I wouldn't change the width - people with ';normal'; monitors will have to scroll horizontally.

2) Just leave the theme the way it is. this isn't ';cleva treva'; it's Wordpress.

3) In IE7 the site looks terrible. In IE8, native or compatibility mode, it looks fine.