Just to add to MonkeyZeus's answer.
Given the speed the internet access in your area you might be able to save a few bucks by eBay'ing a SOHO (small office home office) commercial firewall. Specifically you only need 10/100 not gigabit for internet access, so those old units are virtually worthless for corporate use, hence they usually eBay for around $20.
The setup I am envisioning is:
/-| Printer |
| SAT |---------------| Storage |
| Firewall |---------| Laptop |
| DSL |-/
You should continue to keep the laptop on the WIFI for the Satellite.
You will need to move both the printer and the storage onto that network (reason below).
The firewalls WAN ports are each connected to the two routers.
And the internal connection of the firewall is connected to the laptop.
This will result in a "Double-Nat" situation.
That shouldn't be a problem for internet access, but it will be a problem for the printer and the storage - which is why I said to keep the Wifi connected and move both of them onto that network.
The critical points here are:
The firewall can be configured to send traffic to the relevant route based on port used:
- http/https -> satellite
- RDP -> DSL
The laptop should use the wired connection as its default route as soon as its plugged in (no configuration necessary).
However since the wired connection is on a different IP range the laptop should still use the WIFI to access local services such as the printer and storage.
Back in the day I used to use old Sonicwalls for this, typically either a TZ-170 or TZ-205 - however its been over 7 years since I used them so please don't put to much weight into a particular brand.
A few final thoughts:
This setup is a little complicated, I am only really recommending it to save a few bucks - if you have the money just buy a dual wan router per MonkeyZeus's recommendation.
I have taken setups like this even further by running a VPN over each link.
That allowed me to do asynchronous routing and traffic shaping.
However it required a cloud server to terminate both VPN links and shape the downstream traffic - so unless you really want a "hobby project" thats probably outside the scope of what you are trying to achieve.
The nice thing about this setup is it doesn't require you to change anything on either your existing routers or the laptop. Just plug in the new firewall - if you can't get it working you just unplug it - you will be out $20 but you will be immediately back to where you were - you can't screw anything up.