Yes, you may uninstall it.
I really question why you want to, it would be much easier to run IE and when it asks you if you want IE to be your default browser, you should simply take the yes option.
All machines people are buying today have so much disk memory that you can afford to leave Netscape on them. I find the best reason to do this, is that some websites look better in Netscape.
Also, because Netscape is not targeted for as many of the various viruses, worms, and other of the hackers bags of tricks, you will be less likely to get infected. This does not mean to imply that you will not have these problems, you should still install a good hardware firewall, a good software firewall, a good anti-virus program, a spyware tracker and a popup advertising blocker.
These are all available as individual products (which I prefer) as free or very reasonable downloads, or as prepackaged combination products from companies like McAfee, Norton etc.. (all of which I have tried and abandoned in the past)