debugging

Tbh i'm feeling bad flooding forums with these questions but this is urgent. So, I installed All-In-One WP migration plug in to create a backup, so i could play around changing themes etc. I have downloaded the back up to my pc, played around a bit and then figured out that it's not worth...

Is there any good web debugging tool out there?![FREE MAYBE?!] I know that Fiddler2 is good but it crashes for me when the volume of requests generated is too large to handle. I've also tried WireShark but it's just not user-friendly. I would like to have something that can be used easily. If...