OK, plenty of free HD space.
You should be fine with 2GB of RAM in 10.6. Unless you have a lot of other App's (processes) open that are using all the free RAM, while you are trying to opening Safari or Mail..?
To check your RAM usage, open your Activity Monitor and check to see how much free RAM is there before and after opening Safari or Mail.
If you have a lot of App's open or set to open at Log-in, you may need to cut back on the number of App's that are running at the same time or upgrade your RAM.
before opening mail or safari
Free 1.30 GB; Wired: 268.6 mb: Active 392.2 mb; inactive 58.0 mb; used 717.9 mb
opened mail (which is set up for my comcast account, and only recently has been this crazy) .. first off, it showed "not responding" and took 12 minutes to fully load new messages and get rid of the spinning ball
Free 1.19 gb; wired 276.4 mb; active 473.6 mb; inactive 76.2 mb; used 826.3 mb
Then opened Safari
free 1.08 gb, wired 282.2 mb; active 576.6 mb; inactive 76.5 mb; used 936.9 mb
As I'm typing this:
Free 1,017.5 mb; wired 282.1 mb; active 651.4 mb; inactive 98.6 mb; used 1.01 GB
I hope this makes more sense to you than it does to me ... thanks so far!