and i still dilemma on whether to flash OpenDesire or the Original rooted froyo....

Need to clear something in my mind for flashing steps;

1)Root my device(DONE!)
2)Backup Nandroid
3)Run Titanium Backup
4)Flash my chosen custom ROM
5)Restore files using Titanium Backup again.

a) thats it right? btw whats with the Radio? do i need it? i see some got with radio and some dont. what is it for and why?

b) and about Titanium backup, i just backup all the stuffs, and restore them all just like kan?

c) and all my settings/preferences/options for my apps will not be lose right(for example fonts, colours, etc)?

d) and one more thing, all of my purchased apps from Paid market still be useable kan? or need to download again?

yes, ur step is correct.
a. new radio is needed so that u can use new features from ur phone such as recording 720p.
b. yup
c. u will lose everything after u flash new rom.
d. ur paid apps are are saved in google account, u can always get them back even if u have formatted ur phone. download again or restore from titanium backup.

If u want to flash official froyo, u need to flash the latest radio. For ur apps use titanium to restore.

Am on Win7 x64. Is that the problem ?

Congratulations! I guess the FroYo temptation was too strong to resist. 

Ok, since the Desire users are in ROM flashing mood, I'll just add a friendly reminder here. While there's a very minimal chance of bricking your set when you flash a ROM, flashing a new radio takes the risk to a new level. If there's anything that can brick your set, it's the radio. You can recover from a corrupted ROM, but if you flash a corrupted radio, the only way to fix it is to send your set to HTC.

Do's
- Make sure your battery is full. The last thing you want is the phone shutting down while radio flashing due to low power.
- Check the MD5 hash of the downloaded radio image (or ROM if it includes a radio). Make sure downloaded copy and the one published on the site matches.

Dont's
- Never pull the battery out while the phone is updating the radio. It'll take some time for the updating process to complete. Be patient and wait. Some impatient people thinks that the phone 'hangs' and pulls the battery out to get it to restart. As a result, bricked phone and hello HTC service center.

I've flashed dozens of ROMs on my Hero and N1 but whenever I need to flash a radio, it still sends shivers down my spine. 

Ok so if i want OpenDesire still need new radio or not? no harm using the latest radio right?

Yes, I did. Still it don't work

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Added on August 3, 2010, 8:52 am
I know nothing about Linux

why when i'm using the internet...theres an "H" icon?

Luffy, your torque still dust free?

btw I'm buying a new mSD card, and i found a lot in garage sales but got microSDHC? is that usable on my Desire?

It depends on what connection you use for the internet. When there is a H there, it means you are using the HSDPA connection. If you are connected to a WiFi, the data connection logo will be gone and indicates it is using WiFi connection instead.
When you root and install a custom ROM, usually they will notify you which version of ROM would be the best, if an update is required.

In regards to memory card, MicroSD and MicroSDHC are basically the SAME thing. The HC, indicates HIGH CAPACITY, which is a denotation for any MicroSD cards, that is > 8gb in capacity. Thus, any cards below 8gb will be called MicroSD, while any cards equal or more than 8gb will be called MicroSDHC.

Done rooting usin Win XP x86
x64 ?

Yes. You can.
I'm using SwitchPro to turn it on and off.

Nah, it's fine

I just like messing around with stuffs anyway, but experimenting a ROM take time...

I would say go with the official rooted once first since it's the only one proven working well so far (in this forum by the way)