Probably now a Netscape convert!!!

I'll try to be brief. I once had a very stable PC, only 1.2GB HDD, 16MB RAM, Win95 OSR2, and IE3. I bumped it up to 48MB RAM, everything still cool, but my CAD prog. worked better etc. I foolishly decided to install IE4 and started all sorts of probs with errors, losing my scanner, couldn't detect some install CDS etc....Uninstalled but still was forced to reformat and reinstall Win95 traumatically for my first time! Back to being cool, till I found certain web sites needing IE4 and above. Made numerous queries on forums with varied responses saying IE4 or IE5 will be OK.Finally went for IE5. All seemed OK for a bit, and I liked the browser. I even installed another 13GB HDD. Then whether related or not CAD or Word were taking ages to load and CPU (only P133) semed to be stuck on 100% and everything grinding to a stop. Also my monitor screen was blanking for no apparent reason requiring a reboot to restore. I did all the usual checks changes and monitor swapsies and all seemed to point to a fault on the video card. I finally surrendered and tried the fix all and reformatted and reinstalled.I also had a second hand IBM with a 4GB HDD, 233MMX, and 64MB RAM, which I recently obtained and my daughter was using. I exercised my authority and now I have that computer, but with 13GB partitioned drive. She has the old one with a 4GB HDD.
Guess what! When I installed IE5 on my "new" one it slowed all the loading as before.

I had a copy of Netscape Nav 4.08 on a magazine CD, so installed it. So far it appears far less obtrusive than IE, but possibly a little slower (though that may be just some conjestion on the net at the moment). It hasn't got as many features, or I haven't found them yet. More importantly it hasn't affected my other progs.

I'm probably my own worst enemy by asking the following but here goes:
There is also a copy of Netscape Communicator 4.72 on the CD. and.....
is it worth using instead of Navigator?
how obtrusive is it to the rest of my system?
any known probs with my relatively old and underpowered system?
My daughter is using the P133 and so far no probs yet, though she is not connected on the net.
Any thoughts would be appreciated.
Rod.

PS I also have a slave 1.2 GB HDD on the IBM which I eventually want to install linux on. My daughters and my computer are networked with a crossover lead. Any suggestions on good "free" software to enable her to share and use my modem and internet connection?