Networks Help With Cheap Upgrade to Network

I have an aging home network that I want to upgrade for as little money as possible. I'm hoping you guys can help me.

I have a Linksys WRT400N-RM wireless router, but it's only capable of 100mb/s LAN. I recently purchased a Drobo Pro and have it hooked up to my HTPC via iSCSI, but with the slow speed of the router transfer speeds are incredibly slow and streaming a high-bitrate 1080p movie doesn't work very well.

Can I get a gigabit switch and place it after the router to up the speed between the Drobo and the HTPC, or do I need to get a new router with gigabit capability?

Thanks! Any suggestions/recommendations are helpful in this. It's not my forte and something I haven't looked at since 2010.

 

A small gigabit switch would work between.

 

deathtaker27 speaks the truth.
You should be able to pick up a 8 port GB switch for about fifteen quid.

 

For iSCSI make sure you put it on it's own subnet and ideally it's own network.
It really doesn't like competing with standard data on a LAN