Parallels and Tiger to Leopard (and CoD4...)

I wonder about the procedure to upgrade to latest leopard from tiger x.4.11 with regard to parallels (3). Any hints or tips or links or "best" procedures? Did search around a bit but found nothing really applicable. Can I just upgrade and expect parallels to work as before or do I have to reinstall Parallels with all its content I have now from scratch?
Reason for thinking of an upgrade is that I bought Call of Duty 4 for Mac (after reading some got it to work on Tiger (got the hardware minimum req), but not me...multiplayer works (with the solvable upside down thing) but not single player) and wonder if it is worth getting Leopard and maybe hassle with parallels etc instead of just get a PC copy of CoD4 and run it in the VM (any known problems with CoD4 on Parallels 3.x? Does that work?). Otherwise Tiger and parallels is working great and I wish not to upgrade because of a game. I am waiting for an upgrade ideally until Snowleopard arrives...

Thanks!

J

Parallels 3 build 5626 (XPpro), 10.4.11 on first generation Macbook Pro 17

Not much for a pc gamer, Xbox myself. but... I LOVE COD4!! FRAG OUT!

I doubt you will be able to run CoD4 in virtual windows

I think you should be able to move your virtual machines over to the new system, they are just regular files after all and you can back them up onto an external disk or something

also you can just update your system to leopard without loosing any of your data, not sure what happens to applications though

maybe try some patch for CoD to work under Tiger? multiplayer is the reason to play anyway

If you're satisfied with what you have now, stick with it. The Windows version of Call of Duty is not going to run well in the Parallels VM anyway, so why risk messing everything up? Later on this year (probably around Summer) when Snow Leopard is released, you can make a decision to upgrade. But keep in mind that Snow Leopard will be a kernel upgrade to full 64 bits and may not benefit folks who have older hardware.

Regards.

Thanks

Thanks for your inputs, I will probably leave it as it is and just play the MP version of CoD4 for now.