On my OEM notebook I have both openSUSE-11.4 and debian-squeeze sharing /home and swap.
While on debian OS the machine is working fine on the openSUSE platfporm a ‘lock’ file is continually created in /home/rudra/.mozilla/firefox/3xxxxx/ and internet is slowing down abysmally.
I think Firefox is up to version 7.01 and that is what I would run if I were you. Add the repository above, open Software Management, search on Firefox, switch to the versions Tab and select the bullet for 7.01 (32 or 64 bit as you have installed openSUSE).
I think I have spotted the reason and has erased it. I found that the installed MozillaFirefox has version 8.0-0.2.2 but there was MozillaFirefox-branding-openSUSE version 5.0-14.1 . If that was causing trouble (I am an end-user) I removed it and installed instead MozillaFirefox-branding-upstream version 8.0-2.2 and now for some time the ‘lock’ file has not appeared.
I’ll wait somewhat longer before marking this thread as [SOLVED].