Which Custom ROM should I choose?

Hi there,

I am having a table Simmtronics Xpad X1010 Tablet with following spec-

Brand	Simmtronics
Graphics	Dual Mali-400
Model ID	X1010
Voice Call	No
Processor	1.2 GHz Cortex-A8

RAM

1 GB DDR3

Internal Storage

8 GB

Primary Camera

0.3 megapixels

Display Type

10.1 inch TFT LCD Capacitive Touchscreen with 1024 x 600 pixels ,16 M Colors

Wi-Fi

Yes, 802.11 b/g/n

Battery Type

5600 mAh Lithium - Polymer

USB	Yes, 2 x Micro USB
HDMI	Yes

Operating System

Android 4.0 (Ice Cream Sandwich)

I want to upgrade the Operating system.
1. Can anyone tell me up to which OS I can go?
2. Where I can find that OS?
3. Steps to install that OS?

Thank you.