MacBook - Surfing problem / Leopard install options?

I have a Macbook which I use wirelessly to surf with. Of late an annoying problem seems to have developed where the progress bar seems to stall at about a quarter progress every tenth page or so. Often it then needs to be re-booted. It's becoming a bit of a pain.

I use a Netgear DG834PN and the only things I've changed of late are the channel (to get a stronger signal strength with a Squeezeboxes) and turning off UpNp on the router.

I also played with a network sniffer (can't remember which but it did need to install drivers so after a couple of abortive attempts I decided not to bother - possibly Kismac?). I don't think that any changes were made to the Mac.

I'm wondering what I might try to fix this (other than reverting to the previous and seemingly weaker router channel) or whether an impending install of Leopard could be used to effectively do a reset and give a clean system.

I think that Leopard possibly offers the option to install without doing much else. Will that 'overwrite' method merely leave any problems in there? Or I could perhaps do an archive and install (if it lets me). Will that reset anything to do with drivers/Safari though? I had been waiting as a resut of some of the issues being reported with Leopard (firewall security test failings and other issues) but I may need to bring that forward. I do have a couple of apps that I'd need to do a back-up of the data for (Delicious and Checbook) as I wouldn't want to enter that lot again and I'm wondering what the best option is to be able to load Leopard, give me the healthiest machine, be able to reload my data and hopefully cure this glitch.