That should be more than enough. I'm not sure how many others have kept 6.1 on with a LV 7 install (there have been a few smatterings of install issues w/ LV 7, most notably w/ network installs). If I was the one dealing with it, I'd uninstall all Labview programs from all versions and do a clean LV 7 install and see if that fixes it (with the idea being that if it doesn't, I'd do a format c:, reinstall the OS and then LV 7, but I like to minimize variables when dealing with it). If you are working in XP or Win2k, you can monitor how much memory is being allocated to LV 7 and how much is free, just to see if that's an issue (ctrl-alt-del and use the Task Manager).
2006 Ultimate LabVIEW G-eek.