That will work.

Magic keys are the tools that allow you to open the CD tray of the PS2 without the PS2 realising. They will also only work on a Slimline PS2. If you have an old, big one, you need a slide tool instead of a magic key.

I recommend a modchip over a swap disc though. With a swap disc you have to open the case and swap the discs every time you want to play an import and it gets annoying.
The biggest drawback of swap discs is that you can't play a game with a larger table of contents than the swap disc itself. The last time I checked (around Swap Magic 3.6), the Swap Magic TOC was around 4.25Gb. Any game with a larger TOC won't boot, which ruled out games like MGS2 and Xenosaga. You can occasionally split a larger game over several discs (I managed to extract the ISO, rearrange it and put Xenosaga on three discs), but it's a lengthy and unreliable process. I went through about ten high quality Taiyo Yuden DVD+Rs before I got a bootable disc, and it took most of the spindle to get a playable set of three.