What do I need to take into account when upgrading my motherboard?

I have an: DIXONH55ITX Socket 1156 Advent Firefly FP 3104 System Motherboard

I'm looking to upgrade for 2 main reasons.

1.) Upgrade my Ram, (as the limit of ram for this motherboard is 4gb.)
2.) More than 1 PCI-E slot. (There's only one on this motherboard.)

But my main question is:
What do I need to take into account when upgrading my Motherboard?
(Compatibility issues etc.)

Also any motherboard recommendations (under £200). As I'm planning on upgrading my computer to a gaming rig.

Any replies would be greatly appreciated.

Not quite understanding you. Are you wanting to keep all other parts and just upgrade mobo, ram and gpu?:

It sounds to me like you are wanting to build an entire new system. If so, give us a budget and what should be included (monitor, windows etc.).

That's a relatively old mobo. Depending on your CPU, it may be better to just buy a whole new CPU+MOBO combo.

But, if you wanna keep this original one:
- Need to make sure CPU is compatible.
- If you have RAID arrays using the onboard controller, say bye bye.

Isnt 1156 Sandy Bridge? It isnt that old then. He had a pentium before I am guessing

LGA1155 is Sandy/Ivy. LGA1156 was the other lower-end CPUs when the core i5/i7 first came out.

I may as-well upgrade the Motherboard and CPU with it.. Any suggestions? [The computer itself is only a few years old only about 2-3 years..]

I5 3570K is a good choice. I've paired it with an Asrock PRO MVP H77 mobo.

I tried looking for your mobo. It looks proprietary, if it's got 4GB limit. The stuff I found were systems running core i3. So the above would be a nice upgrade.

Thank you mate!