I had a Time Capsule and it over-heated. I got a free replacement from Apple, but I'm going to replace the drive with a cooler running 'green' one before using it again.
IMO a better option to the Time Capsule is the Apple Airport Extreme Basestation. It's the same thing but without the hard disk. however, you can plug in a USB hard drive and have all the functionality of the Time Capsule (with a bit more wiring), and none of the over-heating. Also the cost of an Airport Extreme and a USB hard drive combined is comparable to the cost of a Time Capsule (maybe £20-30 more)
If you want to do this, get an Airport Extreme, plug it in next to the router and disable the WiFi on the Netgear. Connect the two with a network cable and then the Netgear should basically work only as a modem.
Depends how confident you are with all this stuff really. I didn't find it very difficult at all.