I had a lot of problems using the wordpress website from linux debian recently. I used to use the version of iceweasel (rebranded firefox because name and logo is trademarked despite rest being opensource) which comes along with the debian system and it automatically updated by the debian system.
Iceweasel would freeze for me when using wordpress, especially if trying to view the stats page, or make a post (the most common things I do using the dashboard).
The solution seems to be;
1) use the latest version of the plugin sun’s java in the debian repositories (sun-java-6-plugin not 5). (this is probably not exact name)
2) use the epihany browser rather than iceweasel.