I do not have “TinyMCEComments” and I have the issue on the Presentation widget layout.
I have the Talian 1.0 theme with the following plugins (tested on IE7 and Avant)
[+] Dashboard Editor
[+] del.icio.us widget
[+] Email+ from Grouptivity
[+] email users
[+] Event Calendar
[+] Event Calendar Widget
[+] Front Page Excluded Categories
[+] Get Recent Comments
[+] Google Search widget
[+] Google XML Sitemaps
[+] Identify External Links
[+] IM Online
[+] PictPress
[+] PictPress Archive Pages
[+] PlugInstaller
[+] Presentation Toolkit
[+] RS Discuss
[+] SimplePie Plugin for WordPress
[+] Skinner
[+] Skype Button – Widget
[+] ST Visualize Advanced Features
[+] Sub Pages widget
[+] Subscribe To Comments
[+] This Day on Wikipedia widget
[+] tribe
[+] Vote It Up
[+] WordPress PDA
[+] WordPress Popup Scheduler
[+] wordTube
[+] WP-ContactForm
[+] WP-RSSImport
[+] WP-Sticky
[+] wp-Table
[+] WP-UserOnline
[+] WP-UserOnline Widget
[+] WP Grins
