Rooting my Android smartphone

First a small introduction to the situation.
I bought a Samsung Galaxy S Duos in December. Since this is the first smartphone I've ever bought, I'd been quite happy with all the features up until around a month back. For one the market price went down by nearly Rs.7000, which is approximately a hundred dollars, and secondly thanks to the Internet I began to realise that my phone wasn't even close to being one of the most loaded and powerful phones on the market. All this led to a certain degree of disappointment and regret for not surveying the market more thoroughly and not waiting for the launch of Samsung Galaxy Grand, which seems to be a lot better in all aspects and only slightly more costly than what I had spend.
Anyhow, my biggest gripe with the phone ATM is that I cannot move my applications to the external SD card. My phone memory has become chock full and there's hardly any space left to install anything new.
Now I did read about rooting the phone before, a few weeks after I bought it, but I saw no reason as to why I should risk losing my warranty. Since the past two days though I've been seriously considering it. So now, my question is, does anyone here have any experience with rooting their phones and can give some advice whether I should do it or not. Also if I do root my phone I intend to install a custom ROM. The only one I could find for my model is KyleOpen based on ICS 4.0.4. If anyone knows of another better ROM for the S Duos, I'd be grateful for a link.

I've had 2 Android phones- a DROID X2 and my current phone, a RAZR MAXX.... what can I say? I'm a Motorola fan.

Anyway, I've rooted both of my phones and the process was very simple both times. The only trouble I have is with my MAXX when it installs OTA updates. Most recently, Verizon pushed out Jellybean 4.1.2 and it messed up my root. Then I had to find root utilities made for phones that previously had root instead of using the easier to find utilities to initially root a phone. Once I realized what was going on and why it wasn't working, it really wasn't that big a problem though.

Also, once you root your phone, I highly recommend AdAway- it's an app that modifies your phones hosts file to point known ad servers to non-existent IP addresses. I haven't seen an unwanted popup ad since I installed it.