APC UPS Model Number undecided - Final decision awaited...!!!

Thanks everyone for putting forward their opinion about UPS to my previous post.

I have read all the posts over and over again and finally have decided that I will purchase a UPS from APC.

Now again...few more questions though...????

A LITTLE BACKGROUND THOUGH:

I intend to use UPS for the following desktop:

P4 3 Ghz
3*512 MB RAM
CD DVD R/RW
HDD 160 GB three partitions
HDD 80 GB two partitions
windows xp operating system / windows advanced 2000 server
inkjet printer
d link router
compex switch
creative speaker
motherboard intel 865 GBF
Monitor 17 " LG flat

The application that I currently always use in SAP using Oracle database on windows server 2000 when using 160 GB HDD...

At other times normal surfing using windows xp professional with 80 GB HDD...

WHY I NEED UPS

I need Ups to ensure that when I am using SAP with oracle database...there is no unexpected power outage as it may corrupt SAP software...which is a headache to get installed again...

WHAT I WANT

I want a UPS which can support say 20 - 30 mins so that I can have sometime (normally it takes 10 - 15 mins) to stop server and client in SAP mode...and then exit and shut down the system normally...

I have given a rough configuration of my system so that some knowledgeable person can suggest me with his expertise which one suits my requirements best without burning a hole in my pocket...

IN A NUTSHELL:

In a nutshell, plz suggest which APC model UPS best fits my case balancing between my desire and cost based on above system configurations...?????????????????????

Your time, effort and patience is higly appreciated and will be the basis of my final decision.

warmest regards,

sunando

sunandoghosh at rediffmail dot com

p.s. In India is anyone using Wipro UPS; is it any good...????

disclaimer: you have to say me which model number of product from APC fits my needs best as I am completely non technical and do not understand what Voltage / surge / AV / watt etc etc actually means.......................!

Thanks again for ur help...it is more than appreciated............!!!!!!!!!!!!!!!!

by the way...plz advice keeping in mind...I am also planning to have an inverter...so i believe inverter can support the UPS longer...?????

I REPEAT PLZ GIVE ME EXACT MODEL NO FROM APC OR WIPRO WHICH I SHOULD BUY AS I FAIL TO UNDERSTAND TECHNICAL SPECIFICATIONS.....PLZ....I AM JUST GOING TO SAY TO SHOPKEEPER THE
MODEL NO I WANT....?????????????????