Hi Prima.Vera!
About a year ago I upgraded a kind of similar laptop (at least similar chipset), and here is my info and advice on it:
The model was is a Acer Aspire 9424WSMi. In 2006 when it was bought it had a Core2Duo T5600 (2 x 1.86GHz, 2Megs Cache and 166MHz [667Quad] FSB), 1GB of DDR2 RAM (2 x 512Megs), an 120GB SATA drive with 5400rpm and a GeForce Go 7300. The OS was Windows XP Media Center 2005, that is just a variant of XP with Media Center built in.
Over the past years I upgraded the memory to 2 x 1GB, a 500GB 7200 rpm HDD and went to Windows 7 Pro (32 Bit - don't ask me why).
Finally I upgraded it with the max. CPU the chipset can handle, a Core2Duo T7600 (2 x 2.33GHz, 4Megs Cache and still 166MHz FSB) and a SSD and 2 x 2GB DDR2 RAM.
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So first question
@Prima.Vera , what CPU do you have in there? Still the Core (1) Duo T2500? And what about memory? Still 1GB (2 x 512Megs)?
Getting Win 7 (even 64Bit) to work should be no problem, but some manual driver search since Dell doesn't provide any drivers for that OS. For the 64Bit version you would need a Core 2 Duo since the original Core Duo (like the T2500) lacks of 64Bit support as it is kind of a slapped together Pentium-M (Dothan Core). If it is still a Core Duo the 32Bit version of Win 7 will do just fine.
Some of the drivers like chipset and maybe some network controllers should be already included in Windows 7, some other you may need and want to add manually or update to their latest versions.
Memory should be at least 2GB for Win7. 1.5GB should also do but the more - the better.
To your primary question - SSD:
It IS possible to use a SSD with Windows XP. I would recommend Win 7 or newer because of the already integrated functions and awareness of a solid state drive. But as I said, Win XP should work fine too, with maybe some additional tools that trigger the TRIM function and/or a SSD that has some good garbage collection already built in (most newer SSDs do). There are some guides around the web for installing XP on an SSD. I would check them out if you really want to use XP. The right alignment of the partition also matters, so you may want to create a partition with a proper program or use Win 7(/8/10) or these setup discs on another PC to just create the partition, then installing XP on it without repartitioning it again.
The chipset, or to be exact, the southbridge of the laptop only is the ICH7M variant. Technically it should be able to do SATA II like it's desktop brother but for what reason Intel disabled it and switched back to only SATA I mode. It also doesn't support AHCI that could enable further features like NCQ and native TRIM support even for the integrated AHCI SATA driver in Windows 7 (msahci) that ist already great for a SSD.
So your SSD will be maxed out at a theoretical 150 MB/s and with XP lacking of TRIM support out of the (OS) box.
All in all a SSD in that state still ist a lot faster than a HDD, especially if it still is a 5400 rpm drive. That's because of the fast access times of the SSD.
As for compatibility - initially I used a SanDisk X400 256GB SSD in that old Aspire. I had a issue with it, when I cold booted the laptop it would hang after POST/BIOS screen not recognizing the SSD. A Ctrl+Alt+Del did help and the laptop detected the SSD and booted without a problem. That happend EVERY time I switched on the laptop.
I finally exchanged the X400 with my old Samsung 840 Pro 256GB and the issue was gone. Although the 840 Pro is something like 'pearls before swine' there - it works quite nice.
You do notice that the SSD isn't working as fast as it may could in that laptop, but it is still faster than some rather new laptops still with (maybe even low 5400 rpm) hard disk drives. Not too shabby for a 10 year old laptop (upgraded to it's max.)
Let me / us know about your config and if you need help on finding drivers for Win 7 if you chose to switch to that OS as recommended.
