Mozilla-1.7.7/8 is in current I believe. That should solve some problems you've mentioned.
I've only tried Dropline so I can't comment on the 2 versions of Gnome your talking about. If your looking for a straight up Vanilla Gnome, the Linuce packages work great on Slackware. Thats about as close as your going to come to a traditional Slack Gnome. Actually, I prefer a 'no frills' Gnome. Thats the main reason why I use it because it's straight forward with no eye candy fluff like another WM out there...
If your used to the way Gnome has been on Slack in the past then you should check out Linuce's build.... It comes with some extra themes and such but for the most part is just like Pat used to build... Only better.
There is a link for the 2.10.1 packages at the top of that page.