Hi Manish,
You can install Oracle 10g on Window server 2008 R2.
SAP has provided oracle software 10.2.0.4 Failsafe server 3.4.1.5 Windows 2008.
You can download and install the oracle software.
Also follow the below links as well
Note 1486772 - SAP Systems on Windows Server 2008 R2
http://scn.sap.com/thread/1631150
Let me know if you face any issue out here.
With Regards
Ashutosh Chaturvedi
+919818619396