Try it this way. See link..

Then you may need to look for video/audio IN jacks on the back of your TV. They are RCA jacks colored in yellow for video and red and white for audio (left and right). The back of the Roku has the same jacks, just connect them together with the supplied cable.

http://www.ehow.com/how_4887752_set-up-roku.html

For the router issue I'd consider starting a topic at the roku forum. There may also be some information there that's helpful to you.

http://forums.roku.com/viewforum.php?f=28

if your tv only has 2 HDMI input jacks you may have to plug and unplug devices when you want to use them. If one is used by say a dvd player that you do not use daily then use that HDMI jack for the ROKU and when you want to use the dvd player or whatever needs to plug in switch them out. You will have to select that input on your tv to view what you have plugged in there. Optimally you want to use HDMI connections for the best possible picture quality(HD).

you are using the wireless router that is connected to your internet connection just like your computers are connected to, it has to be able to connect wirelessly to the netflix to stream.

this link is more what you are trying to do since you are doing the wireless setup
How to Set Up Roku Wireless

I also only had two HDMI inputs that were already taken. I thought of a splitter, but decided to just use the RCA cables instead and plug them into one of the other vacant inputs in the back. The picture quality is fine for me with this setup

Once you have the Roku plugged in to the back of one of the tv inputs, and have the tv set to that input, you should have a startup menu on the tv screen where you will need to enter the password for your router, and then the Roku should be able to talk to the tv. The first time I did this hookup, there were just a couple of self-explanatory steps on-screen. The menu shouldn't be disappearing until you do this; if it does, maybe you need to just hit one of the keys on the Roku remote...there aren't that many. Try these suggestions and then report back on your success or failure, please.

Just know that if you do not use HDMI cable you can not get HD quality. I am now spoiled to HD quality on my big tv and would not be happy with out it.

raven-
Roku does not typically deliver in true HD quality regardless of the cable used. I am picky about quality, too, but accept this as a slight limitation with Roku. While the quality I get is not quite HD, it's good enough that it doesn't bother me while watching on a 50" screen. The quality Roku delivers ranges from 1 star (at the minimum connection speed of 0.5 Mbps) to 4 stars (connections over 2.2Mbps). I consistently get 4 stars with my 3 Mbps DSL connection, as long as no one is heavily using one of the other computers in the house that's on the same router.

Can regular phone outlet be used in installation. I have DSL upstairs but it is used with computer.

Thanks for your help

If your TV has a component video connection, you can use this instead of HDMI. It can deliver an HD quality connection. I have used both on my TV and I do not see any difference in the HDMI and Component. Composite connections DO NOT deliver the same quality as Component or HDMI.

A lot of recently reported problems with Roku and Netlfix at Hacking NetFlix : Are You Having Long-Term Streaming Problems? There are enough comments with details that I am reasonably sure this is not an April Fools thread.