I like Firefox the best. It seems to be pretty safe. Netscape, with its builtin IE render looks like the kind of thing that could easily be tricked to render pages like IE instead of firefox, and depending on what OS version and what updates there are to IE this could expose some serious security flaws. Firefox programmers are very quick to fix bugs, compared with MS where it takes them at least till the next "First tuesday" of the month.
Opera is also quite nice, but many web apps don't work so well with it, such as GMail and other similar programs.
i am using opera 7.5 and not 8.52..
because in 8.52 there is a bug..when you are using separate window mode..not tabs.. and when pressing ctrl+n.. the address bar isn't focused..
otherworlds you have to go with mouse or press some keys to get there..
hope this bug will be fixed